Consider the following rule
<rule: str>
( <[token1]> | <[token2]> ) +
the output (%/
) will be the same for the following inputs
input1: <token1> <token2> <token1>
input2: <token1> <token1> <token2>
This is because the 2nd is appended to the first one within a list named 'token1' but there is no hint on the order of matching with respect to other tokens.
Any idea how to get the matching order saved into %/
?
p.s. I have problems compiling my scripts with this %/ magical variable. It always gives me an error on the line following the use of %/
. I assume that the compiler considers it as a beginning of regex without terminating /... Pleas开发者_JAVA百科e let me know if I am using it correctly.
You do it by turning <str>
into <[str]>
so you endup with array in $/->{str}
like this
#!/usr/bin/perl --
use strict; use warnings;
my $jp = do {
use Regexp::Grammars;
qr{
# Keep the big stick handy, just in case...
<debug:on>
<debug:step>
<nocontext: > # Switch on context substring retention
# Match this...
<[str]>+
<rule: str>
( <MATCH=token1> | <MATCH=token2> ) +
<rule: token1> \<token1\>
<rule: token2> \<token2\>
}ixs};
for my $str(
q{input1: <token1> <token2> <token1>},
q{input2: <token1> <token1> <token2>},
) {
print "#<<<<# $str \n\n";
if( $str =~ $jp ){
dd(\%/) ; #/
} else {
print "## fail to match \n";
}
print "\n#>>>>#\n\n";
}
sub dd {
use Data::Dumper;
print Data::Dumper->new([@_])->Useqq(1)->Indent(1)->Dump, "\n";
}
__END__
#<<<<# input1: <token1> <token2> <token1>
$VAR1 = {
"str" => [
"<token1>",
"<token2>",
"<token1>"
]
};
#>>>>#
#<<<<# input2: <token1> <token1> <token2>
$VAR1 = {
"str" => [
"<token1>",
"<token1>",
"<token2>"
]
};
#>>>>#
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