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// re2java $INPUT -o $OUTPUT --input-encoding utf8
// This example supports multiple input encodings: UTF-8 and UTF-32.
// Both lexers are generated from the same rules block, and the use
// blocks add only encoding-specific configurations.
/*!rules:re2c
re2c:yyfill:enable = 0;
re2c:YYPEEK = "yyinput[yycursor]";
re2c:indent:top = 1;
"∀x ∃y" { return true; }
* { return false; }
*/
class Main {
static boolean lex_utf8(int[] yyinput) {
int yycursor = 0;
int yymarker = 0;
/*!use:re2c
re2c:YYCTYPE = "int"; // Java lacks unsigned 8-bit integer type
re2c:encoding:utf8 = 1;
*/
}
static boolean lex_utf32(int[] yyinput) {
int yycursor = 0;
int yymarker = 0;
/*!use:re2c
re2c:YYCTYPE = "int";
re2c:encoding:utf32 = 1;
*/
}
public static void main(String []args) {
// we have to use `int`, because `byte`in Java cannot represent values greater than 127
int[] s_utf8 = new int[]{0xe2, 0x88, 0x80, 0x78, 0x20, 0xe2, 0x88, 0x83, 0x79};
assert lex_utf8(s_utf8);
int[] s_utf32 = new int[]{0x2200, 0x78, 0x20, 0x2203, 0x79};
assert lex_utf32(s_utf32);
}
};
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