Course of Raku / Regexes and grammars / Grammars / The parse tree, make and made / The match tree

Quiz — The match tree

What does the following program print?

grammar Point {
    token TOP { <x> ',' <y> }
    token x   { \d+ }
    token y   { \d+ }
}

say Point.parse('3,4')<y>;
0｢3｣
1｢4｣
0｢3,4｣
0｢y｣

Each token becomes a named branch of the match tree. <y> on the result reaches the y token, which matched 4, so the program prints ｢4｣.

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