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641 lines
10 KiB
641 lines
10 KiB
package brotli
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const (
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transformIdentity = 0
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transformOmitLast1 = 1
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transformOmitLast2 = 2
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transformOmitLast3 = 3
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transformOmitLast4 = 4
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transformOmitLast5 = 5
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transformOmitLast6 = 6
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transformOmitLast7 = 7
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transformOmitLast8 = 8
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transformOmitLast9 = 9
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transformUppercaseFirst = 10
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transformUppercaseAll = 11
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transformOmitFirst1 = 12
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transformOmitFirst2 = 13
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transformOmitFirst3 = 14
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transformOmitFirst4 = 15
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transformOmitFirst5 = 16
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transformOmitFirst6 = 17
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transformOmitFirst7 = 18
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transformOmitFirst8 = 19
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transformOmitFirst9 = 20
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transformShiftFirst = 21
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transformShiftAll = 22 + iota - 22
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numTransformTypes
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)
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const transformsMaxCutOff = transformOmitLast9
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type transforms struct {
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prefix_suffix_size uint16
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prefix_suffix []byte
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prefix_suffix_map []uint16
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num_transforms uint32
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transforms []byte
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params []byte
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cutOffTransforms [transformsMaxCutOff + 1]int16
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}
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func transformPrefixId(t *transforms, I int) byte {
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return t.transforms[(I*3)+0]
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}
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func transformType(t *transforms, I int) byte {
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return t.transforms[(I*3)+1]
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}
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func transformSuffixId(t *transforms, I int) byte {
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return t.transforms[(I*3)+2]
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}
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func transformPrefix(t *transforms, I int) []byte {
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return t.prefix_suffix[t.prefix_suffix_map[transformPrefixId(t, I)]:]
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}
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func transformSuffix(t *transforms, I int) []byte {
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return t.prefix_suffix[t.prefix_suffix_map[transformSuffixId(t, I)]:]
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}
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/* RFC 7932 transforms string data */
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const kPrefixSuffix string = "\001 \002, \010 of the \004 of \002s \001.\005 and \004 " + "in \001\"\004 to \002\">\001\n\002. \001]\005 for \003 a \006 " + "that \001'\006 with \006 from \004 by \001(\006. T" + "he \004 on \004 as \004 is \004ing \002\n\t\001:\003ed " + "\002=\"\004 at \003ly \001,\002='\005.com/\007. This \005" + " not \003er \003al \004ful \004ive \005less \004es" + "t \004ize \002\xc2\xa0\004ous \005 the \002e \000"
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var kPrefixSuffixMap = [50]uint16{
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0x00,
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0x02,
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0x05,
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0x0E,
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0x13,
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0x16,
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0x18,
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0x1E,
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0x23,
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0x25,
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0x2A,
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0x2D,
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0x2F,
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0x32,
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0x34,
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0x3A,
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0x3E,
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0x45,
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0x47,
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0x4E,
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0x55,
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0x5A,
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0x5C,
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0x63,
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0x68,
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0x6D,
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0x72,
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0x77,
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0x7A,
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0x7C,
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0x80,
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0x83,
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0x88,
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0x8C,
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0x8E,
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0x91,
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0x97,
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0x9F,
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0xA5,
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0xA9,
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0xAD,
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0xB2,
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0xB7,
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0xBD,
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0xC2,
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0xC7,
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0xCA,
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0xCF,
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0xD5,
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0xD8,
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}
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/* RFC 7932 transforms */
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var kTransformsData = []byte{
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49,
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transformIdentity,
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49,
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49,
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transformIdentity,
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0,
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0,
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transformIdentity,
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0,
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49,
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transformOmitFirst1,
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49,
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49,
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transformUppercaseFirst,
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0,
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49,
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transformIdentity,
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47,
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0,
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transformIdentity,
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49,
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4,
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transformIdentity,
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0,
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49,
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transformIdentity,
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3,
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49,
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transformUppercaseFirst,
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49,
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49,
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transformIdentity,
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6,
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49,
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transformOmitFirst2,
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49,
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49,
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transformOmitLast1,
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49,
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1,
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transformIdentity,
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0,
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49,
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transformIdentity,
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1,
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0,
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transformUppercaseFirst,
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0,
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49,
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transformIdentity,
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7,
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49,
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transformIdentity,
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9,
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48,
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transformIdentity,
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0,
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49,
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transformIdentity,
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8,
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49,
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transformIdentity,
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5,
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49,
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transformIdentity,
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10,
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49,
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transformIdentity,
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11,
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49,
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transformOmitLast3,
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49,
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49,
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transformIdentity,
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13,
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49,
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transformIdentity,
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14,
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49,
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transformOmitFirst3,
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49,
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49,
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transformOmitLast2,
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49,
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49,
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transformIdentity,
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15,
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49,
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transformIdentity,
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16,
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0,
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transformUppercaseFirst,
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49,
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49,
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transformIdentity,
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12,
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5,
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transformIdentity,
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49,
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0,
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transformIdentity,
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1,
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49,
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transformOmitFirst4,
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49,
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49,
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transformIdentity,
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18,
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49,
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transformIdentity,
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17,
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49,
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transformIdentity,
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19,
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49,
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transformIdentity,
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20,
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49,
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transformOmitFirst5,
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49,
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49,
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transformOmitFirst6,
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49,
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47,
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transformIdentity,
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49,
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49,
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transformOmitLast4,
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49,
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49,
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transformIdentity,
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22,
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49,
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transformUppercaseAll,
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49,
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49,
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transformIdentity,
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23,
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49,
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transformIdentity,
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24,
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49,
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transformIdentity,
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25,
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49,
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transformOmitLast7,
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49,
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49,
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transformOmitLast1,
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26,
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49,
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transformIdentity,
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27,
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49,
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transformIdentity,
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28,
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0,
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transformIdentity,
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12,
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49,
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transformIdentity,
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29,
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49,
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transformOmitFirst9,
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49,
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49,
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transformOmitFirst7,
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49,
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49,
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transformOmitLast6,
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49,
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49,
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transformIdentity,
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21,
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49,
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transformUppercaseFirst,
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1,
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49,
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transformOmitLast8,
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49,
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49,
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transformIdentity,
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31,
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49,
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transformIdentity,
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32,
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47,
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transformIdentity,
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3,
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49,
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transformOmitLast5,
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49,
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49,
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transformOmitLast9,
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49,
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0,
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transformUppercaseFirst,
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1,
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49,
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transformUppercaseFirst,
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8,
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5,
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transformIdentity,
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21,
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49,
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transformUppercaseAll,
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0,
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49,
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transformUppercaseFirst,
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10,
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49,
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transformIdentity,
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30,
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0,
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transformIdentity,
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5,
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35,
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transformIdentity,
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49,
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47,
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transformIdentity,
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2,
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49,
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transformUppercaseFirst,
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17,
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49,
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transformIdentity,
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36,
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49,
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transformIdentity,
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33,
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5,
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transformIdentity,
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0,
|
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49,
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transformUppercaseFirst,
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21,
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|
49,
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transformUppercaseFirst,
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5,
|
|
49,
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transformIdentity,
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37,
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0,
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transformIdentity,
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30,
|
|
49,
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transformIdentity,
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38,
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0,
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transformUppercaseAll,
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0,
|
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49,
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transformIdentity,
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39,
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0,
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transformUppercaseAll,
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49,
|
|
49,
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transformIdentity,
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34,
|
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49,
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transformUppercaseAll,
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8,
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|
49,
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transformUppercaseFirst,
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12,
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0,
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transformIdentity,
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21,
|
|
49,
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transformIdentity,
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40,
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0,
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transformUppercaseFirst,
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12,
|
|
49,
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transformIdentity,
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41,
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49,
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transformIdentity,
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42,
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49,
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transformUppercaseAll,
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17,
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49,
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transformIdentity,
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43,
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0,
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transformUppercaseFirst,
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5,
|
|
49,
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transformUppercaseAll,
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10,
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0,
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transformIdentity,
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34,
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49,
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transformUppercaseFirst,
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33,
|
|
49,
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transformIdentity,
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44,
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49,
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transformUppercaseAll,
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5,
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45,
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transformIdentity,
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49,
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0,
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transformIdentity,
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33,
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49,
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transformUppercaseFirst,
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30,
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49,
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transformUppercaseAll,
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30,
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49,
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transformIdentity,
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46,
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49,
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transformUppercaseAll,
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1,
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49,
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transformUppercaseFirst,
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34,
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0,
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transformUppercaseFirst,
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33,
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0,
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transformUppercaseAll,
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30,
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0,
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transformUppercaseAll,
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1,
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49,
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transformUppercaseAll,
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33,
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49,
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transformUppercaseAll,
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21,
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49,
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transformUppercaseAll,
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12,
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0,
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transformUppercaseAll,
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5,
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49,
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transformUppercaseAll,
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34,
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0,
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transformUppercaseAll,
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12,
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0,
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transformUppercaseFirst,
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30,
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|
0,
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transformUppercaseAll,
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34,
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0,
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transformUppercaseFirst,
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34,
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}
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var kBrotliTransforms = transforms{
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217,
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[]byte(kPrefixSuffix),
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kPrefixSuffixMap[:],
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121,
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kTransformsData,
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nil, /* no extra parameters */
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[transformsMaxCutOff + 1]int16{0, 12, 27, 23, 42, 63, 56, 48, 59, 64},
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}
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func getTransforms() *transforms {
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return &kBrotliTransforms
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}
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func toUpperCase(p []byte) int {
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if p[0] < 0xC0 {
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if p[0] >= 'a' && p[0] <= 'z' {
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p[0] ^= 32
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}
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return 1
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}
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/* An overly simplified uppercasing model for UTF-8. */
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if p[0] < 0xE0 {
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p[1] ^= 32
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return 2
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}
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/* An arbitrary transform for three byte characters. */
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p[2] ^= 5
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return 3
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}
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func shiftTransform(word []byte, word_len int, parameter uint16) int {
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/* Limited sign extension: scalar < (1 << 24). */
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var scalar uint32 = (uint32(parameter) & 0x7FFF) + (0x1000000 - (uint32(parameter) & 0x8000))
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if word[0] < 0x80 {
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/* 1-byte rune / 0sssssss / 7 bit scalar (ASCII). */
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scalar += uint32(word[0])
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word[0] = byte(scalar & 0x7F)
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return 1
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} else if word[0] < 0xC0 {
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/* Continuation / 10AAAAAA. */
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return 1
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} else if word[0] < 0xE0 {
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/* 2-byte rune / 110sssss AAssssss / 11 bit scalar. */
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if word_len < 2 {
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return 1
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}
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scalar += uint32(word[1]&0x3F | (word[0]&0x1F)<<6)
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word[0] = byte(0xC0 | (scalar>>6)&0x1F)
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word[1] = byte(uint32(word[1]&0xC0) | scalar&0x3F)
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return 2
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} else if word[0] < 0xF0 {
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/* 3-byte rune / 1110ssss AAssssss BBssssss / 16 bit scalar. */
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if word_len < 3 {
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return word_len
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}
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scalar += uint32(word[2])&0x3F | uint32(word[1]&0x3F)<<6 | uint32(word[0]&0x0F)<<12
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word[0] = byte(0xE0 | (scalar>>12)&0x0F)
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word[1] = byte(uint32(word[1]&0xC0) | (scalar>>6)&0x3F)
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word[2] = byte(uint32(word[2]&0xC0) | scalar&0x3F)
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return 3
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} else if word[0] < 0xF8 {
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/* 4-byte rune / 11110sss AAssssss BBssssss CCssssss / 21 bit scalar. */
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if word_len < 4 {
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return word_len
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}
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scalar += uint32(word[3])&0x3F | uint32(word[2]&0x3F)<<6 | uint32(word[1]&0x3F)<<12 | uint32(word[0]&0x07)<<18
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word[0] = byte(0xF0 | (scalar>>18)&0x07)
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word[1] = byte(uint32(word[1]&0xC0) | (scalar>>12)&0x3F)
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word[2] = byte(uint32(word[2]&0xC0) | (scalar>>6)&0x3F)
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word[3] = byte(uint32(word[3]&0xC0) | scalar&0x3F)
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return 4
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}
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return 1
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}
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func transformDictionaryWord(dst []byte, word []byte, len int, trans *transforms, transform_idx int) int {
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var idx int = 0
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var prefix []byte = transformPrefix(trans, transform_idx)
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var type_ byte = transformType(trans, transform_idx)
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var suffix []byte = transformSuffix(trans, transform_idx)
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{
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var prefix_len int = int(prefix[0])
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prefix = prefix[1:]
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for {
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tmp1 := prefix_len
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prefix_len--
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if tmp1 == 0 {
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break
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}
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dst[idx] = prefix[0]
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idx++
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prefix = prefix[1:]
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}
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}
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{
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var t int = int(type_)
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var i int = 0
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if t <= transformOmitLast9 {
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len -= t
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} else if t >= transformOmitFirst1 && t <= transformOmitFirst9 {
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var skip int = t - (transformOmitFirst1 - 1)
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word = word[skip:]
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len -= skip
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}
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for i < len {
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dst[idx] = word[i]
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idx++
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i++
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}
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if t == transformUppercaseFirst {
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toUpperCase(dst[idx-len:])
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} else if t == transformUppercaseAll {
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var uppercase []byte = dst
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uppercase = uppercase[idx-len:]
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for len > 0 {
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var step int = toUpperCase(uppercase)
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uppercase = uppercase[step:]
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len -= step
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}
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} else if t == transformShiftFirst {
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var param uint16 = uint16(trans.params[transform_idx*2]) + uint16(trans.params[transform_idx*2+1])<<8
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shiftTransform(dst[idx-len:], int(len), param)
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} else if t == transformShiftAll {
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var param uint16 = uint16(trans.params[transform_idx*2]) + uint16(trans.params[transform_idx*2+1])<<8
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var shift []byte = dst
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shift = shift[idx-len:]
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for len > 0 {
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var step int = shiftTransform(shift, int(len), param)
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shift = shift[step:]
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len -= step
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}
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}
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}
|
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{
|
|
var suffix_len int = int(suffix[0])
|
|
suffix = suffix[1:]
|
|
for {
|
|
tmp2 := suffix_len
|
|
suffix_len--
|
|
if tmp2 == 0 {
|
|
break
|
|
}
|
|
dst[idx] = suffix[0]
|
|
idx++
|
|
suffix = suffix[1:]
|
|
}
|
|
return idx
|
|
}
|
|
}
|
|
|