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// Code generated by re2go, DO NOT EDIT.
//go:generate re2go $INPUT -o $OUTPUT -ci
package main
import "fmt"
const (
yycinit = iota
yycbin
yycdec
yychex
yycoct
)
func Lex(str string) int {
var cursor int
cond := yycinit
n := 0
{
var yych byte
switch (cond) {
case yycinit:
goto yyc_init
case yycbin:
goto yyc_bin
case yycdec:
goto yyc_dec
case yychex:
goto yyc_hex
case yycoct:
goto yyc_oct
default:
panic("internal lexer error")
}
/* *********************************** */
yyc_init:
yych = str[cursor]
switch (yych) {
case '0':
goto yy2
case '1','2','3','4','5','6','7','8','9':
goto yy4
default:
goto yy1
}
yy1:
cursor += 1
{ return -1 }
yy2:
cursor += 1
yych = str[cursor]
switch (yych) {
case 'B':
fallthrough
case 'b':
goto yy5
case 'X':
fallthrough
case 'x':
goto yy6
default:
goto yy3
}
yy3:
cond = yycoct
goto yyc_oct
yy4:
cursor += 1
cursor += -1
cond = yycdec
goto yyc_dec
yy5:
cursor += 1
cond = yycbin
goto yyc_bin
yy6:
cursor += 1
cond = yychex
goto yyc_hex
/* *********************************** */
yyc_bin:
yych = str[cursor]
switch (yych) {
case 0x00:
goto yy8
case '0','1':
goto yy10
default:
goto yy9
}
yy8:
cursor += 1
{ return n }
yy9:
cursor += 1
{ return -1 }
yy10:
cursor += 1
{ n = n*2 + int(str[cursor-1] - '0'); goto yyc_bin; }
/* *********************************** */
yyc_dec:
yych = str[cursor]
switch (yych) {
case 0x00:
goto yy12
case '0','1','2','3','4','5','6','7','8','9':
goto yy14
default:
goto yy13
}
yy12:
cursor += 1
{ return n }
yy13:
cursor += 1
{ return -1 }
yy14:
cursor += 1
{ n = n*10 + int(str[cursor-1] - '0'); goto yyc_dec; }
/* *********************************** */
yyc_hex:
yych = str[cursor]
switch (yych) {
case 0x00:
goto yy16
case '0','1','2','3','4','5','6','7','8','9':
goto yy18
case 'A','B','C','D','E','F':
goto yy19
case 'a','b','c','d','e','f':
goto yy20
default:
goto yy17
}
yy16:
cursor += 1
{ return n }
yy17:
cursor += 1
{ return -1 }
yy18:
cursor += 1
{ n = n*16 + int(str[cursor-1] - '0'); goto yyc_hex; }
yy19:
cursor += 1
{ n = n*16 + int(str[cursor-1] - 'A') + 10; goto yyc_hex; }
yy20:
cursor += 1
{ n = n*16 + int(str[cursor-1] - 'a') + 10; goto yyc_hex; }
/* *********************************** */
yyc_oct:
yych = str[cursor]
switch (yych) {
case 0x00:
goto yy22
case '0','1','2','3','4','5','6','7':
goto yy24
default:
goto yy23
}
yy22:
cursor += 1
{ return n }
yy23:
cursor += 1
{ return -1 }
yy24:
cursor += 1
{ n = n*8 + int(str[cursor-1] - '0'); goto yyc_oct; }
}
}
func test(str string, num int) {
if res := Lex(str); res != num {
panic(fmt.Sprintf("failed %s: expected %d, got %d", str, num, res))
}
}
func main() {
test("123\000", 123)
test("0b101\000", 5)
test("0x10Ff\000", 4096 + 255)
test("0112\000", 74)
test("0\000", 0)
test("\000", -1)
}
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