Re: regex with literal (ie automatically replace '(' with '\(', etc) )

[timotheecour]

something like this, which we should have in std.regex:
string escapeRegex(string a){
        import std.string;
	enum transTable = ['[' : `\[`, '|' : `\|`, '*': `\*`, '+': `\+`, 
'?': `\?`, '(': `\(`, ')': `\)`];
        return translate(a, transTable);
}
string escapeRegexReplace(string a){
        import std.string;
//      enum transTable = ['$' : `$$`, '\\' : `\\`];
        enum transTable = ['$' : `$$`];
        return translate(a, transTable);
}

unittest{
        string a=`asdf(def[ghi]+*|)`;
        assert(match(a,regex(escapeRegex(a))).hit==a);
        string b=`$aa\/$ $$#@$\0$1#$@%#@%=+_`;
        auto s=replace(a,regex(escapeRegex(a)),escapeRegexReplace(b));
        assert(s==b);
}



On Wednesday, 29 May 2013 at 23:28:19 UTC, Timothee Cour wrote:
See below:

import std.stdio;
import std.regex;

void main(){
"h(i".replace!(a=>a.hit~a.hit)(regex(`h\(`,"g")).writeln; 
//this works, but
I need to specify the escape manually
// "h(i".replace!(a=>a.hit~a.hit)(regex(`h(`,"gl")).writeln;  
//I'd like
this to work with a flag, say 'l' (lowercase L) as in 
'litteral'.
}

note, std.array.replace doesn't work because I want to be able 
to use
std.regex' replace with delegate functionality as above.
This is especially useful when the regex's first argument is 
given as an
input argument (ie is unknown), and we want to properly escape 
it.

Alternatively, (and perhaps more generally), could we have a 
function:
string toRegexLiteral(string){
//replace all regex special characters (like '(' ) with their 
escaped
equivalent
}