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Re: validating a quoted string

by choroba (Bishop)
on Jan 13, 2016 at 22:12 UTC ( #1152722=note: print w/replies, xml ) Need Help??


in reply to validating a quoted string

It seems there hasn't been enough Marpa examples today. If you want to validate and split on unquoted space, build a proper parser!
#!/usr/bin/perl use warnings; use strict; use feature qw{ say }; use Marpa::R2; my $dsl = << '__DSL__'; :default ::= action => ::first lexeme default = latm => 1 List ::= Token action => [value] | Token space List action => list Token ::= Naked | Quoted | Quoted Token action => concat | Naked Quoted action => concat | Naked Quoted Token action => concat Quoted ::= ('"') InQ ('"') InQ ::= CharQ InQ action => concat | CharQ CharQ ::= nonq | backslash quote action => second Naked ::= CharO+ action => concat CharO ::= nonqs | backslash quote action => second | backslash single_space action => second backslash ~ [\\] quote ~ '"' single_space ~ [\s] nonq ~ [^"\\]+ nonqs ~ [^"\s\\]+ space ~ [\s]+ __DSL__ sub concat { shift; join q(), @_ } sub list { [ $_[1], @{ $_[3] } ] } sub second { $_[2] } my $grammar = 'Marpa::R2::Scanless::G'->new({ source => \$dsl }); for my $string ( '"ab" "cd"', '"ef" "gh ij"', 'kl mn', 'op "qr st"', '"uv \"wx" yz', 'AB\ CD', 'EF"GH"', '"IJ""KL""MN"', 'OP"QR"\ "ST"UV"WX YZ"\"ABC"DEF"\"GHI\"', '"abc\ def"', '"ghi "jkl"', 'mno "pqr stu', ) { my $v; eval { $v = $grammar->parse(\$string, 'main'); 1 } or warn "invalid $string\n"; say join '|', @$$v if $v; }

Output:

ab|cd ef|gh ij kl|mn op|qr st uv "wx|yz AB CD EFGH IJKLMN OPQR STUVWX YZ"ABCDEF"GHI" invalid "abc\ def" invalid "ghi "jkl" invalid mno "pqr stu
($q=q:Sq=~/;[c](.)(.)/;chr(-||-|5+lengthSq)`"S|oS2"`map{chr |+ord }map{substrSq`S_+|`|}3E|-|`7**2-3:)=~y+S|`+$1,++print+eval$q,q,a,

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