More expansions in template repositories (#10021)
* Super expansion * Explain which features are in 1.11 vs 1.12 * Move imports Signed-off-by: jolheiser <john.olheiser@gmail.com>tokarchuk/v1.17
John Olheiser
5 years ago
committed by
zeripath
parent
206a031b38
commit
28216bde46
@ -0,0 +1,24 @@ |
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# Compiled Object files, Static and Dynamic libs (Shared Objects) |
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*.o |
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*.a |
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*.so |
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|
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# Folders |
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_obj |
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_test |
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|
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# Architecture specific extensions/prefixes |
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*.[568vq] |
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[568vq].out |
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|
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*.cgo1.go |
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*.cgo2.c |
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_cgo_defun.c |
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_cgo_gotypes.go |
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_cgo_export.* |
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|
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_testmain.go |
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|
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*.exe |
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*.test |
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*.prof |
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language: go |
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install: |
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- go get golang.org/x/tools/cmd/cover |
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- go get github.com/mattn/goveralls |
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script: |
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- go test -v -covermode=count -coverprofile=coverage.out |
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- 'if [ "$TRAVIS_PULL_REQUEST" = "false" ] && [ ! -z "$COVERALLS_TOKEN" ]; then $HOME/gopath/bin/goveralls -coverprofile=coverage.out -service=travis-ci -repotoken $COVERALLS_TOKEN; fi' |
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# Contributing # |
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|
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Thanks for your contribution in advance. No matter what you will contribute to this project, pull request or bug report or feature discussion, it's always highly appreciated. |
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## New API or feature ## |
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I want to speak more about how to add new functions to this package. |
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Package `xstring` is a collection of useful string functions which should be implemented in Go. It's a bit subject to say which function should be included and which should not. I set up following rules in order to make it clear and as objective as possible. |
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* Rule 1: Only string algorithm, which takes string as input, can be included. |
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* Rule 2: If a function has been implemented in package `string`, it must not be included. |
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* Rule 3: If a function is not language neutral, it must not be included. |
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* Rule 4: If a function is a part of standard library in other languages, it can be included. |
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* Rule 5: If a function is quite useful in some famous framework or library, it can be included. |
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New function must be discussed in project issues before submitting any code. If a pull request with new functions is sent without any ref issue, it will be rejected. |
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## Pull request ## |
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Pull request is always welcome. Just make sure you have run `go fmt` and all test cases passed before submit. |
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If the pull request is to add a new API or feature, don't forget to update README.md and add new API in function list. |
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@ -0,0 +1,22 @@ |
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The MIT License (MIT) |
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|
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Copyright (c) 2015 Huan Du |
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|
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Permission is hereby granted, free of charge, to any person obtaining a copy |
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of this software and associated documentation files (the "Software"), to deal |
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in the Software without restriction, including without limitation the rights |
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to use, copy, modify, merge, publish, distribute, sublicense, and/or sell |
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copies of the Software, and to permit persons to whom the Software is |
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furnished to do so, subject to the following conditions: |
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|
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The above copyright notice and this permission notice shall be included in all |
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copies or substantial portions of the Software. |
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|
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THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
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IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
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FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE |
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AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
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LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, |
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OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE |
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SOFTWARE. |
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@ -0,0 +1,117 @@ |
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# xstrings # |
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[](https://travis-ci.org/huandu/xstrings) |
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[](https://godoc.org/github.com/huandu/xstrings) |
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[](https://goreportcard.com/report/github.com/huandu/xstrings) |
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[](https://coveralls.io/github/huandu/xstrings?branch=master) |
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|
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Go package [xstrings](https://godoc.org/github.com/huandu/xstrings) is a collection of string functions, which are widely used in other languages but absent in Go package [strings](http://golang.org/pkg/strings). |
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All functions are well tested and carefully tuned for performance. |
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|
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## Propose a new function ## |
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Please review [contributing guideline](CONTRIBUTING.md) and [create new issue](https://github.com/huandu/xstrings/issues) to state why it should be included. |
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## Install ## |
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Use `go get` to install this library. |
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go get github.com/huandu/xstrings |
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## API document ## |
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See [GoDoc](https://godoc.org/github.com/huandu/xstrings) for full document. |
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## Function list ## |
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Go functions have a unique naming style. One, who has experience in other language but new in Go, may have difficulties to find out right string function to use. |
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Here is a list of functions in [strings](http://golang.org/pkg/strings) and [xstrings](https://godoc.org/github.com/huandu/xstrings) with enough extra information about how to map these functions to their friends in other languages. Hope this list could be helpful for fresh gophers. |
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### Package `xstrings` functions ### |
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*Keep this table sorted by Function in ascending order.* |
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| Function | Friends | # | |
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| -------- | ------- | --- | |
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| [Center](https://godoc.org/github.com/huandu/xstrings#Center) | `str.center` in Python; `String#center` in Ruby | [#30](https://github.com/huandu/xstrings/issues/30) | |
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| [Count](https://godoc.org/github.com/huandu/xstrings#Count) | `String#count` in Ruby | [#16](https://github.com/huandu/xstrings/issues/16) | |
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| [Delete](https://godoc.org/github.com/huandu/xstrings#Delete) | `String#delete` in Ruby | [#17](https://github.com/huandu/xstrings/issues/17) | |
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| [ExpandTabs](https://godoc.org/github.com/huandu/xstrings#ExpandTabs) | `str.expandtabs` in Python | [#27](https://github.com/huandu/xstrings/issues/27) | |
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| [FirstRuneToLower](https://godoc.org/github.com/huandu/xstrings#FirstRuneToLower) | `lcfirst` in PHP or Perl | [#15](https://github.com/huandu/xstrings/issues/15) | |
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| [FirstRuneToUpper](https://godoc.org/github.com/huandu/xstrings#FirstRuneToUpper) | `String#capitalize` in Ruby; `ucfirst` in PHP or Perl | [#15](https://github.com/huandu/xstrings/issues/15) | |
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| [Insert](https://godoc.org/github.com/huandu/xstrings#Insert) | `String#insert` in Ruby | [#18](https://github.com/huandu/xstrings/issues/18) | |
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| [LastPartition](https://godoc.org/github.com/huandu/xstrings#LastPartition) | `str.rpartition` in Python; `String#rpartition` in Ruby | [#19](https://github.com/huandu/xstrings/issues/19) | |
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| [LeftJustify](https://godoc.org/github.com/huandu/xstrings#LeftJustify) | `str.ljust` in Python; `String#ljust` in Ruby | [#28](https://github.com/huandu/xstrings/issues/28) | |
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| [Len](https://godoc.org/github.com/huandu/xstrings#Len) | `mb_strlen` in PHP | [#23](https://github.com/huandu/xstrings/issues/23) | |
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| [Partition](https://godoc.org/github.com/huandu/xstrings#Partition) | `str.partition` in Python; `String#partition` in Ruby | [#10](https://github.com/huandu/xstrings/issues/10) | |
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| [Reverse](https://godoc.org/github.com/huandu/xstrings#Reverse) | `String#reverse` in Ruby; `strrev` in PHP; `reverse` in Perl | [#7](https://github.com/huandu/xstrings/issues/7) | |
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| [RightJustify](https://godoc.org/github.com/huandu/xstrings#RightJustify) | `str.rjust` in Python; `String#rjust` in Ruby | [#29](https://github.com/huandu/xstrings/issues/29) | |
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| [RuneWidth](https://godoc.org/github.com/huandu/xstrings#RuneWidth) | - | [#27](https://github.com/huandu/xstrings/issues/27) | |
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| [Scrub](https://godoc.org/github.com/huandu/xstrings#Scrub) | `String#scrub` in Ruby | [#20](https://github.com/huandu/xstrings/issues/20) | |
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| [Shuffle](https://godoc.org/github.com/huandu/xstrings#Shuffle) | `str_shuffle` in PHP | [#13](https://github.com/huandu/xstrings/issues/13) | |
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| [ShuffleSource](https://godoc.org/github.com/huandu/xstrings#ShuffleSource) | `str_shuffle` in PHP | [#13](https://github.com/huandu/xstrings/issues/13) | |
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| [Slice](https://godoc.org/github.com/huandu/xstrings#Slice) | `mb_substr` in PHP | [#9](https://github.com/huandu/xstrings/issues/9) | |
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| [Squeeze](https://godoc.org/github.com/huandu/xstrings#Squeeze) | `String#squeeze` in Ruby | [#11](https://github.com/huandu/xstrings/issues/11) | |
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| [Successor](https://godoc.org/github.com/huandu/xstrings#Successor) | `String#succ` or `String#next` in Ruby | [#22](https://github.com/huandu/xstrings/issues/22) | |
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| [SwapCase](https://godoc.org/github.com/huandu/xstrings#SwapCase) | `str.swapcase` in Python; `String#swapcase` in Ruby | [#12](https://github.com/huandu/xstrings/issues/12) | |
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| [ToCamelCase](https://godoc.org/github.com/huandu/xstrings#ToCamelCase) | `String#camelize` in RoR | [#1](https://github.com/huandu/xstrings/issues/1) | |
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| [ToKebab](https://godoc.org/github.com/huandu/xstrings#ToKebabCase) | - | [#41](https://github.com/huandu/xstrings/issues/41) | |
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| [ToSnakeCase](https://godoc.org/github.com/huandu/xstrings#ToSnakeCase) | `String#underscore` in RoR | [#1](https://github.com/huandu/xstrings/issues/1) | |
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| [Translate](https://godoc.org/github.com/huandu/xstrings#Translate) | `str.translate` in Python; `String#tr` in Ruby; `strtr` in PHP; `tr///` in Perl | [#21](https://github.com/huandu/xstrings/issues/21) | |
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| [Width](https://godoc.org/github.com/huandu/xstrings#Width) | `mb_strwidth` in PHP | [#26](https://github.com/huandu/xstrings/issues/26) | |
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| [WordCount](https://godoc.org/github.com/huandu/xstrings#WordCount) | `str_word_count` in PHP | [#14](https://github.com/huandu/xstrings/issues/14) | |
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| [WordSplit](https://godoc.org/github.com/huandu/xstrings#WordSplit) | - | [#14](https://github.com/huandu/xstrings/issues/14) | |
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|
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### Package `strings` functions ### |
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*Keep this table sorted by Function in ascending order.* |
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|
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| Function | Friends | |
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| -------- | ------- | |
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| [Contains](http://golang.org/pkg/strings/#Contains) | `String#include?` in Ruby | |
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| [ContainsAny](http://golang.org/pkg/strings/#ContainsAny) | - | |
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| [ContainsRune](http://golang.org/pkg/strings/#ContainsRune) | - | |
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| [Count](http://golang.org/pkg/strings/#Count) | `str.count` in Python; `substr_count` in PHP | |
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| [EqualFold](http://golang.org/pkg/strings/#EqualFold) | `stricmp` in PHP; `String#casecmp` in Ruby | |
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| [Fields](http://golang.org/pkg/strings/#Fields) | `str.split` in Python; `split` in Perl; `String#split` in Ruby | |
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| [FieldsFunc](http://golang.org/pkg/strings/#FieldsFunc) | - | |
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| [HasPrefix](http://golang.org/pkg/strings/#HasPrefix) | `str.startswith` in Python; `String#start_with?` in Ruby | |
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| [HasSuffix](http://golang.org/pkg/strings/#HasSuffix) | `str.endswith` in Python; `String#end_with?` in Ruby | |
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| [Index](http://golang.org/pkg/strings/#Index) | `str.index` in Python; `String#index` in Ruby; `strpos` in PHP; `index` in Perl | |
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| [IndexAny](http://golang.org/pkg/strings/#IndexAny) | - | |
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| [IndexByte](http://golang.org/pkg/strings/#IndexByte) | - | |
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| [IndexFunc](http://golang.org/pkg/strings/#IndexFunc) | - | |
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| [IndexRune](http://golang.org/pkg/strings/#IndexRune) | - | |
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| [Join](http://golang.org/pkg/strings/#Join) | `str.join` in Python; `Array#join` in Ruby; `implode` in PHP; `join` in Perl | |
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| [LastIndex](http://golang.org/pkg/strings/#LastIndex) | `str.rindex` in Python; `String#rindex`; `strrpos` in PHP; `rindex` in Perl | |
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| [LastIndexAny](http://golang.org/pkg/strings/#LastIndexAny) | - | |
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| [LastIndexFunc](http://golang.org/pkg/strings/#LastIndexFunc) | - | |
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| [Map](http://golang.org/pkg/strings/#Map) | `String#each_codepoint` in Ruby | |
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| [Repeat](http://golang.org/pkg/strings/#Repeat) | operator `*` in Python and Ruby; `str_repeat` in PHP | |
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| [Replace](http://golang.org/pkg/strings/#Replace) | `str.replace` in Python; `String#sub` in Ruby; `str_replace` in PHP | |
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| [Split](http://golang.org/pkg/strings/#Split) | `str.split` in Python; `String#split` in Ruby; `explode` in PHP; `split` in Perl | |
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| [SplitAfter](http://golang.org/pkg/strings/#SplitAfter) | - | |
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| [SplitAfterN](http://golang.org/pkg/strings/#SplitAfterN) | - | |
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| [SplitN](http://golang.org/pkg/strings/#SplitN) | `str.split` in Python; `String#split` in Ruby; `explode` in PHP; `split` in Perl | |
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| [Title](http://golang.org/pkg/strings/#Title) | `str.title` in Python | |
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| [ToLower](http://golang.org/pkg/strings/#ToLower) | `str.lower` in Python; `String#downcase` in Ruby; `strtolower` in PHP; `lc` in Perl | |
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| [ToLowerSpecial](http://golang.org/pkg/strings/#ToLowerSpecial) | - | |
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| [ToTitle](http://golang.org/pkg/strings/#ToTitle) | - | |
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| [ToTitleSpecial](http://golang.org/pkg/strings/#ToTitleSpecial) | - | |
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| [ToUpper](http://golang.org/pkg/strings/#ToUpper) | `str.upper` in Python; `String#upcase` in Ruby; `strtoupper` in PHP; `uc` in Perl | |
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| [ToUpperSpecial](http://golang.org/pkg/strings/#ToUpperSpecial) | - | |
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| [Trim](http://golang.org/pkg/strings/#Trim) | `str.strip` in Python; `String#strip` in Ruby; `trim` in PHP | |
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| [TrimFunc](http://golang.org/pkg/strings/#TrimFunc) | - | |
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| [TrimLeft](http://golang.org/pkg/strings/#TrimLeft) | `str.lstrip` in Python; `String#lstrip` in Ruby; `ltrim` in PHP | |
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| [TrimLeftFunc](http://golang.org/pkg/strings/#TrimLeftFunc) | - | |
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| [TrimPrefix](http://golang.org/pkg/strings/#TrimPrefix) | - | |
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| [TrimRight](http://golang.org/pkg/strings/#TrimRight) | `str.rstrip` in Python; `String#rstrip` in Ruby; `rtrim` in PHP | |
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| [TrimRightFunc](http://golang.org/pkg/strings/#TrimRightFunc) | - | |
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| [TrimSpace](http://golang.org/pkg/strings/#TrimSpace) | `str.strip` in Python; `String#strip` in Ruby; `trim` in PHP | |
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| [TrimSuffix](http://golang.org/pkg/strings/#TrimSuffix) | `String#chomp` in Ruby; `chomp` in Perl | |
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|
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## License ## |
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This library is licensed under MIT license. See LICENSE for details. |
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@ -0,0 +1,25 @@ |
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// Copyright 2015 Huan Du. All rights reserved.
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// Licensed under the MIT license that can be found in the LICENSE file.
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package xstrings |
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import ( |
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"bytes" |
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) |
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const bufferMaxInitGrowSize = 2048 |
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|
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// Lazy initialize a buffer.
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func allocBuffer(orig, cur string) *bytes.Buffer { |
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output := &bytes.Buffer{} |
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maxSize := len(orig) * 4 |
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|
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// Avoid to reserve too much memory at once.
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if maxSize > bufferMaxInitGrowSize { |
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maxSize = bufferMaxInitGrowSize |
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} |
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output.Grow(maxSize) |
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output.WriteString(orig[:len(orig)-len(cur)]) |
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return output |
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} |
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@ -0,0 +1,404 @@ |
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// Copyright 2015 Huan Du. All rights reserved.
|
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// Licensed under the MIT license that can be found in the LICENSE file.
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|
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package xstrings |
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import ( |
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"bytes" |
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"math/rand" |
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"unicode" |
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"unicode/utf8" |
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) |
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|
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// ToCamelCase is to convert words separated by space, underscore and hyphen to camel case.
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//
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// Some samples.
|
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// "some_words" => "SomeWords"
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// "http_server" => "HttpServer"
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// "no_https" => "NoHttps"
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// "_complex__case_" => "_Complex_Case_"
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// "some words" => "SomeWords"
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func ToCamelCase(str string) string { |
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if len(str) == 0 { |
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return "" |
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} |
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buf := &bytes.Buffer{} |
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var r0, r1 rune |
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var size int |
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// leading connector will appear in output.
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for len(str) > 0 { |
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r0, size = utf8.DecodeRuneInString(str) |
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str = str[size:] |
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|
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if !isConnector(r0) { |
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r0 = unicode.ToUpper(r0) |
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break |
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} |
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buf.WriteRune(r0) |
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} |
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|
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if len(str) == 0 { |
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// A special case for a string contains only 1 rune.
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if size != 0 { |
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buf.WriteRune(r0) |
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} |
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return buf.String() |
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} |
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|
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for len(str) > 0 { |
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r1 = r0 |
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r0, size = utf8.DecodeRuneInString(str) |
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str = str[size:] |
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|
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if isConnector(r0) && isConnector(r1) { |
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buf.WriteRune(r1) |
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continue |
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} |
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|
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if isConnector(r1) { |
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r0 = unicode.ToUpper(r0) |
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} else { |
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r0 = unicode.ToLower(r0) |
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buf.WriteRune(r1) |
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} |
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} |
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|
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buf.WriteRune(r0) |
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return buf.String() |
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} |
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// ToSnakeCase can convert all upper case characters in a string to
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// snake case format.
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//
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// Some samples.
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// "FirstName" => "first_name"
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// "HTTPServer" => "http_server"
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// "NoHTTPS" => "no_https"
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// "GO_PATH" => "go_path"
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// "GO PATH" => "go_path" // space is converted to underscore.
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// "GO-PATH" => "go_path" // hyphen is converted to underscore.
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// "HTTP2XX" => "http_2xx" // insert an underscore before a number and after an alphabet.
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// "http2xx" => "http_2xx"
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// "HTTP20xOK" => "http_20x_ok"
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func ToSnakeCase(str string) string { |
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return camelCaseToLowerCase(str, '_') |
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} |
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|
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// ToKebabCase can convert all upper case characters in a string to
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// kebab case format.
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//
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// Some samples.
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// "FirstName" => "first-name"
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// "HTTPServer" => "http-server"
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// "NoHTTPS" => "no-https"
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// "GO_PATH" => "go-path"
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// "GO PATH" => "go-path" // space is converted to '-'.
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// "GO-PATH" => "go-path" // hyphen is converted to '-'.
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// "HTTP2XX" => "http-2xx" // insert a '-' before a number and after an alphabet.
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// "http2xx" => "http-2xx"
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// "HTTP20xOK" => "http-20x-ok"
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func ToKebabCase(str string) string { |
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return camelCaseToLowerCase(str, '-') |
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} |
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|
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func camelCaseToLowerCase(str string, connector rune) string { |
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if len(str) == 0 { |
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return "" |
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} |
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|
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buf := &bytes.Buffer{} |
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var prev, r0, r1 rune |
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var size int |
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|
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r0 = connector |
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|
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for len(str) > 0 { |
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prev = r0 |
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r0, size = utf8.DecodeRuneInString(str) |
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str = str[size:] |
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|
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switch { |
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case r0 == utf8.RuneError: |
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buf.WriteRune(r0) |
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|
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case unicode.IsUpper(r0): |
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if prev != connector && !unicode.IsNumber(prev) { |
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buf.WriteRune(connector) |
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} |
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|
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buf.WriteRune(unicode.ToLower(r0)) |
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|
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if len(str) == 0 { |
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break |
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} |
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|
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r0, size = utf8.DecodeRuneInString(str) |
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str = str[size:] |
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|
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if !unicode.IsUpper(r0) { |
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buf.WriteRune(r0) |
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break |
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} |
||||
|
||||
// find next non-upper-case character and insert connector properly.
|
||||
// it's designed to convert `HTTPServer` to `http_server`.
|
||||
// if there are more than 2 adjacent upper case characters in a word,
|
||||
// treat them as an abbreviation plus a normal word.
|
||||
for len(str) > 0 { |
||||
r1 = r0 |
||||
r0, size = utf8.DecodeRuneInString(str) |
||||
str = str[size:] |
||||
|
||||
if r0 == utf8.RuneError { |
||||
buf.WriteRune(unicode.ToLower(r1)) |
||||
buf.WriteRune(r0) |
||||
break |
||||
} |
||||
|
||||
if !unicode.IsUpper(r0) { |
||||
if isConnector(r0) { |
||||
r0 = connector |
||||
|
||||
buf.WriteRune(unicode.ToLower(r1)) |
||||
} else if unicode.IsNumber(r0) { |
||||
// treat a number as an upper case rune
|
||||
// so that both `http2xx` and `HTTP2XX` can be converted to `http_2xx`.
|
||||
buf.WriteRune(unicode.ToLower(r1)) |
||||
buf.WriteRune(connector) |
||||
buf.WriteRune(r0) |
||||
} else { |
||||
buf.WriteRune(connector) |
||||
buf.WriteRune(unicode.ToLower(r1)) |
||||
buf.WriteRune(r0) |
||||
} |
||||
|
||||
break |
||||
} |
||||
|
||||
buf.WriteRune(unicode.ToLower(r1)) |
||||
} |
||||
|
||||
if len(str) == 0 || r0 == connector { |
||||
buf.WriteRune(unicode.ToLower(r0)) |
||||
} |
||||
|
||||
case unicode.IsNumber(r0): |
||||
if prev != connector && !unicode.IsNumber(prev) { |
||||
buf.WriteRune(connector) |
||||
} |
||||
|
||||
buf.WriteRune(r0) |
||||
|
||||
default: |
||||
if isConnector(r0) { |
||||
r0 = connector |
||||
} |
||||
|
||||
buf.WriteRune(r0) |
||||
} |
||||
} |
||||
|
||||
return buf.String() |
||||
} |
||||
|
||||
func isConnector(r rune) bool { |
||||
return r == '-' || r == '_' || unicode.IsSpace(r) |
||||
} |
||||
|
||||
// SwapCase will swap characters case from upper to lower or lower to upper.
|
||||
func SwapCase(str string) string { |
||||
var r rune |
||||
var size int |
||||
|
||||
buf := &bytes.Buffer{} |
||||
|
||||
for len(str) > 0 { |
||||
r, size = utf8.DecodeRuneInString(str) |
||||
|
||||
switch { |
||||
case unicode.IsUpper(r): |
||||
buf.WriteRune(unicode.ToLower(r)) |
||||
|
||||
case unicode.IsLower(r): |
||||
buf.WriteRune(unicode.ToUpper(r)) |
||||
|
||||
default: |
||||
buf.WriteRune(r) |
||||
} |
||||
|
||||
str = str[size:] |
||||
} |
||||
|
||||
return buf.String() |
||||
} |
||||
|
||||
// FirstRuneToUpper converts first rune to upper case if necessary.
|
||||
func FirstRuneToUpper(str string) string { |
||||
if str == "" { |
||||
return str |
||||
} |
||||
|
||||
r, size := utf8.DecodeRuneInString(str) |
||||
|
||||
if !unicode.IsLower(r) { |
||||
return str |
||||
} |
||||
|
||||
buf := &bytes.Buffer{} |
||||
buf.WriteRune(unicode.ToUpper(r)) |
||||
buf.WriteString(str[size:]) |
||||
return buf.String() |
||||
} |
||||
|
||||
// FirstRuneToLower converts first rune to lower case if necessary.
|
||||
func FirstRuneToLower(str string) string { |
||||
if str == "" { |
||||
return str |
||||
} |
||||
|
||||
r, size := utf8.DecodeRuneInString(str) |
||||
|
||||
if !unicode.IsUpper(r) { |
||||
return str |
||||
} |
||||
|
||||
buf := &bytes.Buffer{} |
||||
buf.WriteRune(unicode.ToLower(r)) |
||||
buf.WriteString(str[size:]) |
||||
return buf.String() |
||||
} |
||||
|
||||
// Shuffle randomizes runes in a string and returns the result.
|
||||
// It uses default random source in `math/rand`.
|
||||
func Shuffle(str string) string { |
||||
if str == "" { |
||||
return str |
||||
} |
||||
|
||||
runes := []rune(str) |
||||
index := 0 |
||||
|
||||
for i := len(runes) - 1; i > 0; i-- { |
||||
index = rand.Intn(i + 1) |
||||
|
||||
if i != index { |
||||
runes[i], runes[index] = runes[index], runes[i] |
||||
} |
||||
} |
||||
|
||||
return string(runes) |
||||
} |
||||
|
||||
// ShuffleSource randomizes runes in a string with given random source.
|
||||
func ShuffleSource(str string, src rand.Source) string { |
||||
if str == "" { |
||||
return str |
||||
} |
||||
|
||||
runes := []rune(str) |
||||
index := 0 |
||||
r := rand.New(src) |
||||
|
||||
for i := len(runes) - 1; i > 0; i-- { |
||||
index = r.Intn(i + 1) |
||||
|
||||
if i != index { |
||||
runes[i], runes[index] = runes[index], runes[i] |
||||
} |
||||
} |
||||
|
||||
return string(runes) |
||||
} |
||||
|
||||
// Successor returns the successor to string.
|
||||
//
|
||||
// If there is one alphanumeric rune is found in string, increase the rune by 1.
|
||||
// If increment generates a "carry", the rune to the left of it is incremented.
|
||||
// This process repeats until there is no carry, adding an additional rune if necessary.
|
||||
//
|
||||
// If there is no alphanumeric rune, the rightmost rune will be increased by 1
|
||||
// regardless whether the result is a valid rune or not.
|
||||
//
|
||||
// Only following characters are alphanumeric.
|
||||
// * a - z
|
||||
// * A - Z
|
||||
// * 0 - 9
|
||||
//
|
||||
// Samples (borrowed from ruby's String#succ document):
|
||||
// "abcd" => "abce"
|
||||
// "THX1138" => "THX1139"
|
||||
// "<<koala>>" => "<<koalb>>"
|
||||
// "1999zzz" => "2000aaa"
|
||||
// "ZZZ9999" => "AAAA0000"
|
||||
// "***" => "**+"
|
||||
func Successor(str string) string { |
||||
if str == "" { |
||||
return str |
||||
} |
||||
|
||||
var r rune |
||||
var i int |
||||
carry := ' ' |
||||
runes := []rune(str) |
||||
l := len(runes) |
||||
lastAlphanumeric := l |
||||
|
||||
for i = l - 1; i >= 0; i-- { |
||||
r = runes[i] |
||||
|
||||
if ('a' <= r && r <= 'y') || |
||||
('A' <= r && r <= 'Y') || |
||||
('0' <= r && r <= '8') { |
||||
runes[i]++ |
||||
carry = ' ' |
||||
lastAlphanumeric = i |
||||
break |
||||
} |
||||
|
||||
switch r { |
||||
case 'z': |
||||
runes[i] = 'a' |
||||
carry = 'a' |
||||
lastAlphanumeric = i |
||||
|
||||
case 'Z': |
||||
runes[i] = 'A' |
||||
carry = 'A' |
||||
lastAlphanumeric = i |
||||
|
||||
case '9': |
||||
runes[i] = '0' |
||||
carry = '0' |
||||
lastAlphanumeric = i |
||||
} |
||||
} |
||||
|
||||
// Needs to add one character for carry.
|
||||
if i < 0 && carry != ' ' { |
||||
buf := &bytes.Buffer{} |
||||
buf.Grow(l + 4) // Reserve enough space for write.
|
||||
|
||||
if lastAlphanumeric != 0 { |
||||
buf.WriteString(str[:lastAlphanumeric]) |
||||
} |
||||
|
||||
buf.WriteRune(carry) |
||||
|
||||
for _, r = range runes[lastAlphanumeric:] { |
||||
buf.WriteRune(r) |
||||
} |
||||
|
||||
return buf.String() |
||||
} |
||||
|
||||
// No alphanumeric character. Simply increase last rune's value.
|
||||
if lastAlphanumeric == l { |
||||
runes[l-1]++ |
||||
} |
||||
|
||||
return string(runes) |
||||
} |
||||
@ -0,0 +1,120 @@ |
||||
// Copyright 2015 Huan Du. All rights reserved.
|
||||
// Licensed under the MIT license that can be found in the LICENSE file.
|
||||
|
||||
package xstrings |
||||
|
||||
import ( |
||||
"unicode" |
||||
"unicode/utf8" |
||||
) |
||||
|
||||
// Len returns str's utf8 rune length.
|
||||
func Len(str string) int { |
||||
return utf8.RuneCountInString(str) |
||||
} |
||||
|
||||
// WordCount returns number of words in a string.
|
||||
//
|
||||
// Word is defined as a locale dependent string containing alphabetic characters,
|
||||
// which may also contain but not start with `'` and `-` characters.
|
||||
func WordCount(str string) int { |
||||
var r rune |
||||
var size, n int |
||||
|
||||
inWord := false |
||||
|
||||
for len(str) > 0 { |
||||
r, size = utf8.DecodeRuneInString(str) |
||||
|
||||
switch { |
||||
case isAlphabet(r): |
||||
if !inWord { |
||||
inWord = true |
||||
n++ |
||||
} |
||||
|
||||
case inWord && (r == '\'' || r == '-'): |
||||
// Still in word.
|
||||
|
||||
default: |
||||
inWord = false |
||||
} |
||||
|
||||
str = str[size:] |
||||
} |
||||
|
||||
return n |
||||
} |
||||
|
||||
const minCJKCharacter = '\u3400' |
||||
|
||||
// Checks r is a letter but not CJK character.
|
||||
func isAlphabet(r rune) bool { |
||||
if !unicode.IsLetter(r) { |
||||
return false |
||||
} |
||||
|
||||
switch { |
||||
// Quick check for non-CJK character.
|
||||
case r < minCJKCharacter: |
||||
return true |
||||
|
||||
// Common CJK characters.
|
||||
case r >= '\u4E00' && r <= '\u9FCC': |
||||
return false |
||||
|
||||
// Rare CJK characters.
|
||||
case r >= '\u3400' && r <= '\u4D85': |
||||
return false |
||||
|
||||
// Rare and historic CJK characters.
|
||||
case r >= '\U00020000' && r <= '\U0002B81D': |
||||
return false |
||||
} |
||||
|
||||
return true |
||||
} |
||||
|
||||
// Width returns string width in monotype font.
|
||||
// Multi-byte characters are usually twice the width of single byte characters.
|
||||
//
|
||||
// Algorithm comes from `mb_strwidth` in PHP.
|
||||
// http://php.net/manual/en/function.mb-strwidth.php
|
||||
func Width(str string) int { |
||||
var r rune |
||||
var size, n int |
||||
|
||||
for len(str) > 0 { |
||||
r, size = utf8.DecodeRuneInString(str) |
||||
n += RuneWidth(r) |
||||
str = str[size:] |
||||
} |
||||
|
||||
return n |
||||
} |
||||
|
||||
// RuneWidth returns character width in monotype font.
|
||||
// Multi-byte characters are usually twice the width of single byte characters.
|
||||
//
|
||||
// Algorithm comes from `mb_strwidth` in PHP.
|
||||
// http://php.net/manual/en/function.mb-strwidth.php
|
||||
func RuneWidth(r rune) int { |
||||
switch { |
||||
case r == utf8.RuneError || r < '\x20': |
||||
return 0 |
||||
|
||||
case '\x20' <= r && r < '\u2000': |
||||
return 1 |
||||
|
||||
case '\u2000' <= r && r < '\uFF61': |
||||
return 2 |
||||
|
||||
case '\uFF61' <= r && r < '\uFFA0': |
||||
return 1 |
||||
|
||||
case '\uFFA0' <= r: |
||||
return 2 |
||||
} |
||||
|
||||
return 0 |
||||
} |
||||
@ -0,0 +1,8 @@ |
||||
// Copyright 2015 Huan Du. All rights reserved.
|
||||
// Licensed under the MIT license that can be found in the LICENSE file.
|
||||
|
||||
// Package xstrings is to provide string algorithms which are useful but not included in `strings` package.
|
||||
// See project home page for details. https://github.com/huandu/xstrings
|
||||
//
|
||||
// Package xstrings assumes all strings are encoded in utf8.
|
||||
package xstrings |
||||
@ -0,0 +1,170 @@ |
||||
// Copyright 2015 Huan Du. All rights reserved.
|
||||
// Licensed under the MIT license that can be found in the LICENSE file.
|
||||
|
||||
package xstrings |
||||
|
||||
import ( |
||||
"bytes" |
||||
"unicode/utf8" |
||||
) |
||||
|
||||
// ExpandTabs can expand tabs ('\t') rune in str to one or more spaces dpending on
|
||||
// current column and tabSize.
|
||||
// The column number is reset to zero after each newline ('\n') occurring in the str.
|
||||
//
|
||||
// ExpandTabs uses RuneWidth to decide rune's width.
|
||||
// For example, CJK characters will be treated as two characters.
|
||||
//
|
||||
// If tabSize <= 0, ExpandTabs panics with error.
|
||||
//
|
||||
// Samples:
|
||||
// ExpandTabs("a\tbc\tdef\tghij\tk", 4) => "a bc def ghij k"
|
||||
// ExpandTabs("abcdefg\thij\nk\tl", 4) => "abcdefg hij\nk l"
|
||||
// ExpandTabs("z中\t文\tw", 4) => "z中 文 w"
|
||||
func ExpandTabs(str string, tabSize int) string { |
||||
if tabSize <= 0 { |
||||
panic("tab size must be positive") |
||||
} |
||||
|
||||
var r rune |
||||
var i, size, column, expand int |
||||
var output *bytes.Buffer |
||||
|
||||
orig := str |
||||
|
||||
for len(str) > 0 { |
||||
r, size = utf8.DecodeRuneInString(str) |
||||
|
||||
if r == '\t' { |
||||
expand = tabSize - column%tabSize |
||||
|
||||
if output == nil { |
||||
output = allocBuffer(orig, str) |
||||
} |
||||
|
||||
for i = 0; i < expand; i++ { |
||||
output.WriteByte(byte(' ')) |
||||
} |
||||
|
||||
column += expand |
||||
} else { |
||||
if r == '\n' { |
||||
column = 0 |
||||
} else { |
||||
column += RuneWidth(r) |
||||
} |
||||
|
||||
if output != nil { |
||||
output.WriteRune(r) |
||||
} |
||||
} |
||||
|
||||
str = str[size:] |
||||
} |
||||
|
||||
if output == nil { |
||||
return orig |
||||
} |
||||
|
||||
return output.String() |
||||
} |
||||
|
||||
// LeftJustify returns a string with pad string at right side if str's rune length is smaller than length.
|
||||
// If str's rune length is larger than length, str itself will be returned.
|
||||
//
|
||||
// If pad is an empty string, str will be returned.
|
||||
//
|
||||
// Samples:
|
||||
// LeftJustify("hello", 4, " ") => "hello"
|
||||
// LeftJustify("hello", 10, " ") => "hello "
|
||||
// LeftJustify("hello", 10, "123") => "hello12312"
|
||||
func LeftJustify(str string, length int, pad string) string { |
||||
l := Len(str) |
||||
|
||||
if l >= length || pad == "" { |
||||
return str |
||||
} |
||||
|
||||
remains := length - l |
||||
padLen := Len(pad) |
||||
|
||||
output := &bytes.Buffer{} |
||||
output.Grow(len(str) + (remains/padLen+1)*len(pad)) |
||||
output.WriteString(str) |
||||
writePadString(output, pad, padLen, remains) |
||||
return output.String() |
||||
} |
||||
|
||||
// RightJustify returns a string with pad string at left side if str's rune length is smaller than length.
|
||||
// If str's rune length is larger than length, str itself will be returned.
|
||||
//
|
||||
// If pad is an empty string, str will be returned.
|
||||
//
|
||||
// Samples:
|
||||
// RightJustify("hello", 4, " ") => "hello"
|
||||
// RightJustify("hello", 10, " ") => " hello"
|
||||
// RightJustify("hello", 10, "123") => "12312hello"
|
||||
func RightJustify(str string, length int, pad string) string { |
||||
l := Len(str) |
||||
|
||||
if l >= length || pad == "" { |
||||
return str |
||||
} |
||||
|
||||
remains := length - l |
||||
padLen := Len(pad) |
||||
|
||||
output := &bytes.Buffer{} |
||||
output.Grow(len(str) + (remains/padLen+1)*len(pad)) |
||||
writePadString(output, pad, padLen, remains) |
||||
output.WriteString(str) |
||||
return output.String() |
||||
} |
||||
|
||||
// Center returns a string with pad string at both side if str's rune length is smaller than length.
|
||||
// If str's rune length is larger than length, str itself will be returned.
|
||||
//
|
||||
// If pad is an empty string, str will be returned.
|
||||
//
|
||||
// Samples:
|
||||
// Center("hello", 4, " ") => "hello"
|
||||
// Center("hello", 10, " ") => " hello "
|
||||
// Center("hello", 10, "123") => "12hello123"
|
||||
func Center(str string, length int, pad string) string { |
||||
l := Len(str) |
||||
|
||||
if l >= length || pad == "" { |
||||
return str |
||||
} |
||||
|
||||
remains := length - l |
||||
padLen := Len(pad) |
||||
|
||||
output := &bytes.Buffer{} |
||||
output.Grow(len(str) + (remains/padLen+1)*len(pad)) |
||||
writePadString(output, pad, padLen, remains/2) |
||||
output.WriteString(str) |
||||
writePadString(output, pad, padLen, (remains+1)/2) |
||||
return output.String() |
||||
} |
||||
|
||||
func writePadString(output *bytes.Buffer, pad string, padLen, remains int) { |
||||
var r rune |
||||
var size int |
||||
|
||||
repeats := remains / padLen |
||||
|
||||
for i := 0; i < repeats; i++ { |
||||
output.WriteString(pad) |
||||
} |
||||
|
||||
remains = remains % padLen |
||||
|
||||
if remains != 0 { |
||||
for i := 0; i < remains; i++ { |
||||
r, size = utf8.DecodeRuneInString(pad) |
||||
output.WriteRune(r) |
||||
pad = pad[size:] |
||||
} |
||||
} |
||||
} |
||||
@ -0,0 +1,3 @@ |
||||
module github.com/huandu/xstrings |
||||
|
||||
go 1.12 |
||||
@ -0,0 +1,217 @@ |
||||
// Copyright 2015 Huan Du. All rights reserved.
|
||||
// Licensed under the MIT license that can be found in the LICENSE file.
|
||||
|
||||
package xstrings |
||||
|
||||
import ( |
||||
"bytes" |
||||
"strings" |
||||
"unicode/utf8" |
||||
) |
||||
|
||||
// Reverse a utf8 encoded string.
|
||||
func Reverse(str string) string { |
||||
var size int |
||||
|
||||
tail := len(str) |
||||
buf := make([]byte, tail) |
||||
s := buf |
||||
|
||||
for len(str) > 0 { |
||||
_, size = utf8.DecodeRuneInString(str) |
||||
tail -= size |
||||
s = append(s[:tail], []byte(str[:size])...) |
||||
str = str[size:] |
||||
} |
||||
|
||||
return string(buf) |
||||
} |
||||
|
||||
// Slice a string by rune.
|
||||
//
|
||||
// Start must satisfy 0 <= start <= rune length.
|
||||
//
|
||||
// End can be positive, zero or negative.
|
||||
// If end >= 0, start and end must satisfy start <= end <= rune length.
|
||||
// If end < 0, it means slice to the end of string.
|
||||
//
|
||||
// Otherwise, Slice will panic as out of range.
|
||||
func Slice(str string, start, end int) string { |
||||
var size, startPos, endPos int |
||||
|
||||
origin := str |
||||
|
||||
if start < 0 || end > len(str) || (end >= 0 && start > end) { |
||||
panic("out of range") |
||||
} |
||||
|
||||
if end >= 0 { |
||||
end -= start |
||||
} |
||||
|
||||
for start > 0 && len(str) > 0 { |
||||
_, size = utf8.DecodeRuneInString(str) |
||||
start-- |
||||
startPos += size |
||||
str = str[size:] |
||||
} |
||||
|
||||
if end < 0 { |
||||
return origin[startPos:] |
||||
} |
||||
|
||||
endPos = startPos |
||||
|
||||
for end > 0 && len(str) > 0 { |
||||
_, size = utf8.DecodeRuneInString(str) |
||||
end-- |
||||
endPos += size |
||||
str = str[size:] |
||||
} |
||||
|
||||
if len(str) == 0 && (start > 0 || end > 0) { |
||||
panic("out of range") |
||||
} |
||||
|
||||
return origin[startPos:endPos] |
||||
} |
||||
|
||||
// Partition splits a string by sep into three parts.
|
||||
// The return value is a slice of strings with head, match and tail.
|
||||
//
|
||||
// If str contains sep, for example "hello" and "l", Partition returns
|
||||
// "he", "l", "lo"
|
||||
//
|
||||
// If str doesn't contain sep, for example "hello" and "x", Partition returns
|
||||
// "hello", "", ""
|
||||
func Partition(str, sep string) (head, match, tail string) { |
||||
index := strings.Index(str, sep) |
||||
|
||||
if index == -1 { |
||||
head = str |
||||
return |
||||
} |
||||
|
||||
head = str[:index] |
||||
match = str[index : index+len(sep)] |
||||
tail = str[index+len(sep):] |
||||
return |
||||
} |
||||
|
||||
// LastPartition splits a string by last instance of sep into three parts.
|
||||
// The return value is a slice of strings with head, match and tail.
|
||||
//
|
||||
// If str contains sep, for example "hello" and "l", LastPartition returns
|
||||
// "hel", "l", "o"
|
||||
//
|
||||
// If str doesn't contain sep, for example "hello" and "x", LastPartition returns
|
||||
// "", "", "hello"
|
||||
func LastPartition(str, sep string) (head, match, tail string) { |
||||
index := strings.LastIndex(str, sep) |
||||
|
||||
if index == -1 { |
||||
tail = str |
||||
return |
||||
} |
||||
|
||||
head = str[:index] |
||||
match = str[index : index+len(sep)] |
||||
tail = str[index+len(sep):] |
||||
return |
||||
} |
||||
|
||||
// Insert src into dst at given rune index.
|
||||
// Index is counted by runes instead of bytes.
|
||||
//
|
||||
// If index is out of range of dst, panic with out of range.
|
||||
func Insert(dst, src string, index int) string { |
||||
return Slice(dst, 0, index) + src + Slice(dst, index, -1) |
||||
} |
||||
|
||||
// Scrub scrubs invalid utf8 bytes with repl string.
|
||||
// Adjacent invalid bytes are replaced only once.
|
||||
func Scrub(str, repl string) string { |
||||
var buf *bytes.Buffer |
||||
var r rune |
||||
var size, pos int |
||||
var hasError bool |
||||
|
||||
origin := str |
||||
|
||||
for len(str) > 0 { |
||||
r, size = utf8.DecodeRuneInString(str) |
||||
|
||||
if r == utf8.RuneError { |
||||
if !hasError { |
||||
if buf == nil { |
||||
buf = &bytes.Buffer{} |
||||
} |
||||
|
||||
buf.WriteString(origin[:pos]) |
||||
hasError = true |
||||
} |
||||
} else if hasError { |
||||
hasError = false |
||||
buf.WriteString(repl) |
||||
|
||||
origin = origin[pos:] |
||||
pos = 0 |
||||
} |
||||
|
||||
pos += size |
||||
str = str[size:] |
||||
} |
||||
|
||||
if buf != nil { |
||||
buf.WriteString(origin) |
||||
return buf.String() |
||||
} |
||||
|
||||
// No invalid byte.
|
||||
return origin |
||||
} |
||||
|
||||
// WordSplit splits a string into words. Returns a slice of words.
|
||||
// If there is no word in a string, return nil.
|
||||
//
|
||||
// Word is defined as a locale dependent string containing alphabetic characters,
|
||||
// which may also contain but not start with `'` and `-` characters.
|
||||
func WordSplit(str string) []string { |
||||
var word string |
||||
var words []string |
||||
var r rune |
||||
var size, pos int |
||||
|
||||
inWord := false |
||||
|
||||
for len(str) > 0 { |
||||
r, size = utf8.DecodeRuneInString(str) |
||||
|
||||
switch { |
||||
case isAlphabet(r): |
||||
if !inWord { |
||||
inWord = true |
||||
word = str |
||||
pos = 0 |
||||
} |
||||
|
||||
case inWord && (r == '\'' || r == '-'): |
||||
// Still in word.
|
||||
|
||||
default: |
||||
if inWord { |
||||
inWord = false |
||||
words = append(words, word[:pos]) |
||||
} |
||||
} |
||||
|
||||
pos += size |
||||
str = str[size:] |
||||
} |
||||
|
||||
if inWord { |
||||
words = append(words, word[:pos]) |
||||
} |
||||
|
||||
return words |
||||
} |
||||
@ -0,0 +1,547 @@ |
||||
// Copyright 2015 Huan Du. All rights reserved.
|
||||
// Licensed under the MIT license that can be found in the LICENSE file.
|
||||
|
||||
package xstrings |
||||
|
||||
import ( |
||||
"bytes" |
||||
"unicode" |
||||
"unicode/utf8" |
||||
) |
||||
|
||||
type runeRangeMap struct { |
||||
FromLo rune // Lower bound of range map.
|
||||
FromHi rune // An inclusive higher bound of range map.
|
||||
ToLo rune |
||||
ToHi rune |
||||
} |
||||
|
||||
type runeDict struct { |
||||
Dict [unicode.MaxASCII + 1]rune |
||||
} |
||||
|
||||
type runeMap map[rune]rune |
||||
|
||||
// Translator can translate string with pre-compiled from and to patterns.
|
||||
// If a from/to pattern pair needs to be used more than once, it's recommended
|
||||
// to create a Translator and reuse it.
|
||||
type Translator struct { |
||||
quickDict *runeDict // A quick dictionary to look up rune by index. Only available for latin runes.
|
||||
runeMap runeMap // Rune map for translation.
|
||||
ranges []*runeRangeMap // Ranges of runes.
|
||||
mappedRune rune // If mappedRune >= 0, all matched runes are translated to the mappedRune.
|
||||
reverted bool // If to pattern is empty, all matched characters will be deleted.
|
||||
hasPattern bool |
||||
} |
||||
|
||||
// NewTranslator creates new Translator through a from/to pattern pair.
|
||||
func NewTranslator(from, to string) *Translator { |
||||
tr := &Translator{} |
||||
|
||||
if from == "" { |
||||
return tr |
||||
} |
||||
|
||||
reverted := from[0] == '^' |
||||
deletion := len(to) == 0 |
||||
|
||||
if reverted { |
||||
from = from[1:] |
||||
} |
||||
|
||||
var fromStart, fromEnd, fromRangeStep rune |
||||
var toStart, toEnd, toRangeStep rune |
||||
var fromRangeSize, toRangeSize rune |
||||
var singleRunes []rune |
||||
|
||||
// Update the to rune range.
|
||||
updateRange := func() { |
||||
// No more rune to read in the to rune pattern.
|
||||
if toEnd == utf8.RuneError { |
||||
return |
||||
} |
||||
|
||||
if toRangeStep == 0 { |
||||
to, toStart, toEnd, toRangeStep = nextRuneRange(to, toEnd) |
||||
return |
||||
} |
||||
|
||||
// Current range is not empty. Consume 1 rune from start.
|
||||
if toStart != toEnd { |
||||
toStart += toRangeStep |
||||
return |
||||
} |
||||
|
||||
// No more rune. Repeat the last rune.
|
||||
if to == "" { |
||||
toEnd = utf8.RuneError |
||||
return |
||||
} |
||||
|
||||
// Both start and end are used. Read two more runes from the to pattern.
|
||||
to, toStart, toEnd, toRangeStep = nextRuneRange(to, utf8.RuneError) |
||||
} |
||||
|
||||
if deletion { |
||||
toStart = utf8.RuneError |
||||
toEnd = utf8.RuneError |
||||
} else { |
||||
// If from pattern is reverted, only the last rune in the to pattern will be used.
|
||||
if reverted { |
||||
var size int |
||||
|
||||
for len(to) > 0 { |
||||
toStart, size = utf8.DecodeRuneInString(to) |
||||
to = to[size:] |
||||
} |
||||
|
||||
toEnd = utf8.RuneError |
||||
} else { |
||||
to, toStart, toEnd, toRangeStep = nextRuneRange(to, utf8.RuneError) |
||||
} |
||||
} |
||||
|
||||
fromEnd = utf8.RuneError |
||||
|
||||
for len(from) > 0 { |
||||
from, fromStart, fromEnd, fromRangeStep = nextRuneRange(from, fromEnd) |
||||
|
||||
// fromStart is a single character. Just map it with a rune in the to pattern.
|
||||
if fromRangeStep == 0 { |
||||
singleRunes = tr.addRune(fromStart, toStart, singleRunes) |
||||
updateRange() |
||||
continue |
||||
} |
||||
|
||||
for toEnd != utf8.RuneError && fromStart != fromEnd { |
||||
// If mapped rune is a single character instead of a range, simply shift first
|
||||
// rune in the range.
|
||||
if toRangeStep == 0 { |
||||
singleRunes = tr.addRune(fromStart, toStart, singleRunes) |
||||
updateRange() |
||||
fromStart += fromRangeStep |
||||
continue |
||||
} |
||||
|
||||
fromRangeSize = (fromEnd - fromStart) * fromRangeStep |
||||
toRangeSize = (toEnd - toStart) * toRangeStep |
||||
|
||||
// Not enough runes in the to pattern. Need to read more.
|
||||
if fromRangeSize > toRangeSize { |
||||
fromStart, toStart = tr.addRuneRange(fromStart, fromStart+toRangeSize*fromRangeStep, toStart, toEnd, singleRunes) |
||||
fromStart += fromRangeStep |
||||
updateRange() |
||||
|
||||
// Edge case: If fromRangeSize == toRangeSize + 1, the last fromStart value needs be considered
|
||||
// as a single rune.
|
||||
if fromStart == fromEnd { |
||||
singleRunes = tr.addRune(fromStart, toStart, singleRunes) |
||||
updateRange() |
||||
} |
||||
|
||||
continue |
||||
} |
||||
|
||||
fromStart, toStart = tr.addRuneRange(fromStart, fromEnd, toStart, toStart+fromRangeSize*toRangeStep, singleRunes) |
||||
updateRange() |
||||
break |
||||
} |
||||
|
||||
if fromStart == fromEnd { |
||||
fromEnd = utf8.RuneError |
||||
continue |
||||
} |
||||
|
||||
fromStart, toStart = tr.addRuneRange(fromStart, fromEnd, toStart, toStart, singleRunes) |
||||
fromEnd = utf8.RuneError |
||||
} |
||||
|
||||
if fromEnd != utf8.RuneError { |
||||
singleRunes = tr.addRune(fromEnd, toStart, singleRunes) |
||||
} |
||||
|
||||
tr.reverted = reverted |
||||
tr.mappedRune = -1 |
||||
tr.hasPattern = true |
||||
|
||||
// Translate RuneError only if in deletion or reverted mode.
|
||||
if deletion || reverted { |
||||
tr.mappedRune = toStart |
||||
} |
||||
|
||||
return tr |
||||
} |
||||
|
||||
func (tr *Translator) addRune(from, to rune, singleRunes []rune) []rune { |
||||
if from <= unicode.MaxASCII { |
||||
if tr.quickDict == nil { |
||||
tr.quickDict = &runeDict{} |
||||
} |
||||
|
||||
tr.quickDict.Dict[from] = to |
||||
} else { |
||||
if tr.runeMap == nil { |
||||
tr.runeMap = make(runeMap) |
||||
} |
||||
|
||||
tr.runeMap[from] = to |
||||
} |
||||
|
||||
singleRunes = append(singleRunes, from) |
||||
return singleRunes |
||||
} |
||||
|
||||
func (tr *Translator) addRuneRange(fromLo, fromHi, toLo, toHi rune, singleRunes []rune) (rune, rune) { |
||||
var r rune |
||||
var rrm *runeRangeMap |
||||
|
||||
if fromLo < fromHi { |
||||
rrm = &runeRangeMap{ |
||||
FromLo: fromLo, |
||||
FromHi: fromHi, |
||||
ToLo: toLo, |
||||
ToHi: toHi, |
||||
} |
||||
} else { |
||||
rrm = &runeRangeMap{ |
||||
FromLo: fromHi, |
||||
FromHi: fromLo, |
||||
ToLo: toHi, |
||||
ToHi: toLo, |
||||
} |
||||
} |
||||
|
||||
// If there is any single rune conflicts with this rune range, clear single rune record.
|
||||
for _, r = range singleRunes { |
||||
if rrm.FromLo <= r && r <= rrm.FromHi { |
||||
if r <= unicode.MaxASCII { |
||||
tr.quickDict.Dict[r] = 0 |
||||
} else { |
||||
delete(tr.runeMap, r) |
||||
} |
||||
} |
||||
} |
||||
|
||||
tr.ranges = append(tr.ranges, rrm) |
||||
return fromHi, toHi |
||||
} |
||||
|
||||
func nextRuneRange(str string, last rune) (remaining string, start, end rune, rangeStep rune) { |
||||
var r rune |
||||
var size int |
||||
|
||||
remaining = str |
||||
escaping := false |
||||
isRange := false |
||||
|
||||
for len(remaining) > 0 { |
||||
r, size = utf8.DecodeRuneInString(remaining) |
||||
remaining = remaining[size:] |
||||
|
||||
// Parse special characters.
|
||||
if !escaping { |
||||
if r == '\\' { |
||||
escaping = true |
||||
continue |
||||
} |
||||
|
||||
if r == '-' { |
||||
// Ignore slash at beginning of string.
|
||||
if last == utf8.RuneError { |
||||
continue |
||||
} |
||||
|
||||
start = last |
||||
isRange = true |
||||
continue |
||||
} |
||||
} |
||||
|
||||
escaping = false |
||||
|
||||
if last != utf8.RuneError { |
||||
// This is a range which start and end are the same.
|
||||
// Considier it as a normal character.
|
||||
if isRange && last == r { |
||||
isRange = false |
||||
continue |
||||
} |
||||
|
||||
start = last |
||||
end = r |
||||
|
||||
if isRange { |
||||
if start < end { |
||||
rangeStep = 1 |
||||
} else { |
||||
rangeStep = -1 |
||||
} |
||||
} |
||||
|
||||
return |
||||
} |
||||
|
||||
last = r |
||||
} |
||||
|
||||
start = last |
||||
end = utf8.RuneError |
||||
return |
||||
} |
||||
|
||||
// Translate str with a from/to pattern pair.
|
||||
//
|
||||
// See comment in Translate function for usage and samples.
|
||||
func (tr *Translator) Translate(str string) string { |
||||
if !tr.hasPattern || str == "" { |
||||
return str |
||||
} |
||||
|
||||
var r rune |
||||
var size int |
||||
var needTr bool |
||||
|
||||
orig := str |
||||
|
||||
var output *bytes.Buffer |
||||
|
||||
for len(str) > 0 { |
||||
r, size = utf8.DecodeRuneInString(str) |
||||
r, needTr = tr.TranslateRune(r) |
||||
|
||||
if needTr && output == nil { |
||||
output = allocBuffer(orig, str) |
||||
} |
||||
|
||||
if r != utf8.RuneError && output != nil { |
||||
output.WriteRune(r) |
||||
} |
||||
|
||||
str = str[size:] |
||||
} |
||||
|
||||
// No character is translated.
|
||||
if output == nil { |
||||
return orig |
||||
} |
||||
|
||||
return output.String() |
||||
} |
||||
|
||||
// TranslateRune return translated rune and true if r matches the from pattern.
|
||||
// If r doesn't match the pattern, original r is returned and translated is false.
|
||||
func (tr *Translator) TranslateRune(r rune) (result rune, translated bool) { |
||||
switch { |
||||
case tr.quickDict != nil: |
||||
if r <= unicode.MaxASCII { |
||||
result = tr.quickDict.Dict[r] |
||||
|
||||
if result != 0 { |
||||
translated = true |
||||
|
||||
if tr.mappedRune >= 0 { |
||||
result = tr.mappedRune |
||||
} |
||||
|
||||
break |
||||
} |
||||
} |
||||
|
||||
fallthrough |
||||
|
||||
case tr.runeMap != nil: |
||||
var ok bool |
||||
|
||||
if result, ok = tr.runeMap[r]; ok { |
||||
translated = true |
||||
|
||||
if tr.mappedRune >= 0 { |
||||
result = tr.mappedRune |
||||
} |
||||
|
||||
break |
||||
} |
||||
|
||||
fallthrough |
||||
|
||||
default: |
||||
var rrm *runeRangeMap |
||||
ranges := tr.ranges |
||||
|
||||
for i := len(ranges) - 1; i >= 0; i-- { |
||||
rrm = ranges[i] |
||||
|
||||
if rrm.FromLo <= r && r <= rrm.FromHi { |
||||
translated = true |
||||
|
||||
if tr.mappedRune >= 0 { |
||||
result = tr.mappedRune |
||||
break |
||||
} |
||||
|
||||
if rrm.ToLo < rrm.ToHi { |
||||
result = rrm.ToLo + r - rrm.FromLo |
||||
} else if rrm.ToLo > rrm.ToHi { |
||||
// ToHi can be smaller than ToLo if range is from higher to lower.
|
||||
result = rrm.ToLo - r + rrm.FromLo |
||||
} else { |
||||
result = rrm.ToLo |
||||
} |
||||
|
||||
break |
||||
} |
||||
} |
||||
} |
||||
|
||||
if tr.reverted { |
||||
if !translated { |
||||
result = tr.mappedRune |
||||
} |
||||
|
||||
translated = !translated |
||||
} |
||||
|
||||
if !translated { |
||||
result = r |
||||
} |
||||
|
||||
return |
||||
} |
||||
|
||||
// HasPattern returns true if Translator has one pattern at least.
|
||||
func (tr *Translator) HasPattern() bool { |
||||
return tr.hasPattern |
||||
} |
||||
|
||||
// Translate str with the characters defined in from replaced by characters defined in to.
|
||||
//
|
||||
// From and to are patterns representing a set of characters. Pattern is defined as following.
|
||||
//
|
||||
// * Special characters
|
||||
// * '-' means a range of runes, e.g.
|
||||
// * "a-z" means all characters from 'a' to 'z' inclusive;
|
||||
// * "z-a" means all characters from 'z' to 'a' inclusive.
|
||||
// * '^' as first character means a set of all runes excepted listed, e.g.
|
||||
// * "^a-z" means all characters except 'a' to 'z' inclusive.
|
||||
// * '\' escapes special characters.
|
||||
// * Normal character represents itself, e.g. "abc" is a set including 'a', 'b' and 'c'.
|
||||
//
|
||||
// Translate will try to find a 1:1 mapping from from to to.
|
||||
// If to is smaller than from, last rune in to will be used to map "out of range" characters in from.
|
||||
//
|
||||
// Note that '^' only works in the from pattern. It will be considered as a normal character in the to pattern.
|
||||
//
|
||||
// If the to pattern is an empty string, Translate works exactly the same as Delete.
|
||||
//
|
||||
// Samples:
|
||||
// Translate("hello", "aeiou", "12345") => "h2ll4"
|
||||
// Translate("hello", "a-z", "A-Z") => "HELLO"
|
||||
// Translate("hello", "z-a", "a-z") => "svool"
|
||||
// Translate("hello", "aeiou", "*") => "h*ll*"
|
||||
// Translate("hello", "^l", "*") => "**ll*"
|
||||
// Translate("hello ^ world", `\^lo`, "*") => "he*** * w*r*d"
|
||||
func Translate(str, from, to string) string { |
||||
tr := NewTranslator(from, to) |
||||
return tr.Translate(str) |
||||
} |
||||
|
||||
// Delete runes in str matching the pattern.
|
||||
// Pattern is defined in Translate function.
|
||||
//
|
||||
// Samples:
|
||||
// Delete("hello", "aeiou") => "hll"
|
||||
// Delete("hello", "a-k") => "llo"
|
||||
// Delete("hello", "^a-k") => "he"
|
||||
func Delete(str, pattern string) string { |
||||
tr := NewTranslator(pattern, "") |
||||
return tr.Translate(str) |
||||
} |
||||
|
||||
// Count how many runes in str match the pattern.
|
||||
// Pattern is defined in Translate function.
|
||||
//
|
||||
// Samples:
|
||||
// Count("hello", "aeiou") => 3
|
||||
// Count("hello", "a-k") => 3
|
||||
// Count("hello", "^a-k") => 2
|
||||
func Count(str, pattern string) int { |
||||
if pattern == "" || str == "" { |
||||
return 0 |
||||
} |
||||
|
||||
var r rune |
||||
var size int |
||||
var matched bool |
||||
|
||||
tr := NewTranslator(pattern, "") |
||||
cnt := 0 |
||||
|
||||
for len(str) > 0 { |
||||
r, size = utf8.DecodeRuneInString(str) |
||||
str = str[size:] |
||||
|
||||
if _, matched = tr.TranslateRune(r); matched { |
||||
cnt++ |
||||
} |
||||
} |
||||
|
||||
return cnt |
||||
} |
||||
|
||||
// Squeeze deletes adjacent repeated runes in str.
|
||||
// If pattern is not empty, only runes matching the pattern will be squeezed.
|
||||
//
|
||||
// Samples:
|
||||
// Squeeze("hello", "") => "helo"
|
||||
// Squeeze("hello", "m-z") => "hello"
|
||||
// Squeeze("hello world", " ") => "hello world"
|
||||
func Squeeze(str, pattern string) string { |
||||
var last, r rune |
||||
var size int |
||||
var skipSqueeze, matched bool |
||||
var tr *Translator |
||||
var output *bytes.Buffer |
||||
|
||||
orig := str |
||||
last = -1 |
||||
|
||||
if len(pattern) > 0 { |
||||
tr = NewTranslator(pattern, "") |
||||
} |
||||
|
||||
for len(str) > 0 { |
||||
r, size = utf8.DecodeRuneInString(str) |
||||
|
||||
// Need to squeeze the str.
|
||||
if last == r && !skipSqueeze { |
||||
if tr != nil { |
||||
if _, matched = tr.TranslateRune(r); !matched { |
||||
skipSqueeze = true |
||||
} |
||||
} |
||||
|
||||
if output == nil { |
||||
output = allocBuffer(orig, str) |
||||
} |
||||
|
||||
if skipSqueeze { |
||||
output.WriteRune(r) |
||||
} |
||||
} else { |
||||
if output != nil { |
||||
output.WriteRune(r) |
||||
} |
||||
|
||||
last = r |
||||
skipSqueeze = false |
||||
} |
||||
|
||||
str = str[size:] |
||||
} |
||||
|
||||
if output == nil { |
||||
return orig |
||||
} |
||||
|
||||
return output.String() |
||||
} |
||||
Loading…
Reference in new issue