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// re2zig $INPUT -o $OUTPUT
const std = @import("std");
%{rules:x
$ { return 0; }
* { return 1; }
[a] $ { return 2; }
[a] { return 3; }
[b] $ | [b] { return 4; }
[c]+ $ { return 5; }
%}
fn lex_simple(yyinput: [:0]const u8) i32 {
var yycursor: usize = 0;
var yymarker: usize = 0;
const yylimit: usize = yyinput.len;
%{use:x
re2c:yyfill:enable = 0;
%}
}
fn lex_eof(yyinput: [:0]const u8) i32 {
var yycursor: usize = 0;
var yymarker: usize = 0;
const yylimit: usize = yyinput.len;
%{use:x
re2c:eof = 0;
re2c:YYFILL = "false";
re2c:YYEND = "yycursor == yylimit";
%}
}
%{max %}
fn lex_scc(str: [:0]const u8) !i32 {
var yycursor: usize = 0;
var yymarker: usize = 0;
const end: usize = str.len;
const yylimit: usize = end + yymaxfill;
var yyinput = try std.testing.allocator.alloc(u8, yylimit);
defer std.testing.allocator.free(yyinput);
std.mem.copyForwards(u8, yyinput[0..], str);
std.mem.copyForwards(u8, yyinput[end..], &[_]u8{0} ** yymaxfill);
%{use:x
re2c:YYFILL = "return -1;";
re2c:YYEND = "yycursor == end";
%}
}
fn run(str: [:0]const u8, ret: i32) !void {
try std.testing.expectEqual(lex_simple(str), ret);
try std.testing.expectEqual(lex_eof(str), ret);
try std.testing.expectEqual(try lex_scc(str), ret);
}
test {
try run("", 0);
try run("a", 2);
try run("ax", 3);
try run("b", 4);
try run("bx", 4);
try run("ccc", 5);
}
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