JavaScript create regex programmatically -

i know can create javascript replace this:

str = str.replace(/mytarget/g, 'some value');

that replace occurrences of literal mytarget. however, have big array of words/phrases want use in regex replace, , regexps language elements (they not wrapped in string when declaring), can't find way declare regexps programmatically unless hard-code them. if have:

var arr=['word', 'another', 'hello'];

i want produce:

str = str.replace(/word/g, 'some value');

str = str.replace(/another/g, 'some value');

str = str.replace(/hello/g, 'some value');

please post example can use regexps, i'll adding more expressions regexps such whitespace etc. need regexp way. finally, please don't offer using eval, i'm sure there better way.

you need invoke regexp constructor function that. example:

['word', 'another', 'hello'].foreach(function( word ) {     var myexp = new regexp(word, 'g');     str = str.replace(myexp, 'some value'); }); 

the first argument constructor string, literally takes wrap inbetween //. second paramter string, can pass modifiers g, i, etc.