#!/usr/bin/perl -w # Test clean_tree use strict; use Test::More tests => 3; use_ok qw( Parse::Eyapp ); use_ok qw( Parse::Eyapp::Treeregexp ); #use Data::Dumper; my $translationscheme = q{ %{ # head code is available at tree construction time #use Data::Dumper; %} %defaultaction { $lhs->{n} = $_[1]->{n} } %metatree %left '-' '+' %left '*' %left NEG %% line: %name EXP exp ; exp: %name PLUS exp.left '+' exp.right { $lhs->{n} .= $left->{n} + $right->{n} } | %name TIMES exp.left '*' exp.right { $lhs->{n} = $left->{n} * $right->{n} } | %name NUM $NUM { $lhs->{n} = $NUM->{attr} } | '(' $exp ')' %begin { $exp } | %name MINUS exp.left '-' exp.right { $lhs->{n} = $left->{n} - $right->{n} } | %name UMINUS '-' $exp %prec NEG { $lhs->{n} = -$exp->{n} } ; %% # tail code is available at tree construction time sub _Error { die "Syntax error.\n"; } sub _Lexer { my($parser)=shift; $parser->YYData->{INPUT} or return('',undef); $parser->YYData->{INPUT}=~s/^\s*//; for ($parser->YYData->{INPUT}) { s/^([0-9]+(?:\.[0-9]+)?)// and return('NUM',$1); s/^([A-Za-z][A-Za-z0-9_]*)// and return('VAR',$1); s/^(.)// and return($1,$1); s/^\s*//; } } sub Run { my($self)=shift; return $self->YYParse( yylex => \&_Lexer, yyerror => \&_Error ); } }; # end translation scheme sub is_syntactic_terminal { my $self = shift; return (ref($self) eq 'TERMINAL') and exists($self->{token}) and exists($self->{attr}) and ($self->{token} eq $self->{attr}); } Parse::Eyapp->new_grammar( input=>$translationscheme, classname=>'Calc', firstline =>7, # outputfile => 'Calc.pm' ); my $parser = Calc->new(); # Create the parser $parser->YYData->{INPUT} = "2*(3-3)\n"; # Set the input my $t = $parser->Run; # Parse it #$Data::Dumper::Indent = 1; #$Data::Dumper::Terse = 1; #$Data::Dumper::Deepcopy = 1; #print Dumper($t); # Show the tree # Get the AST $t->clean_tree(sub { (ref($_[0]) eq 'CODE') or is_syntactic_terminal($_[0]) }); #print Dumper($t); # Show the tree my $expected_tree = bless( { 'children' => [ bless( { 'children' => [ bless( { 'children' => [] }, 'NUM' ), bless( { 'children' => [ bless( { 'children' => [] }, 'NUM' ), bless( { 'children' => [] }, 'NUM' ) ] }, 'MINUS' ) ] }, 'TIMES' ) ] }, 'EXP' ); is_deeply($t, $expected_tree, "clean_tree");