parse.p6

#!/usr/bin/env perl6

use Grammar::Tracer;
# use Grammar::Debugger;

grammar Offsides {
  token TOP {
    <tree>*
  }

  token tree {
    $<indent>=(\s*) <text>
    <subtree($<indent>)>*
  }

  token subtree($current-indent) {

    # PROBLEM: This never has anything in it!
    { say "Current indent: [$current-indent]" }

    $current-indent $<more-indent>=(\s+) <text>

    # Might have some sub-trees with more indent
    <tree($current-indent ~ ~$<more-indent>)>*
  }

  token text {
    \S .*? $$
  }
}

my $test-input = q|
hello
  this is
    a
  test to see
  if this
        can calculate
        the offside
  rule
|;

my $match = Offsides.parse($test-input);

say $match;