Trailing Whitespace (Per Line) in JS
Match trailing spaces and tabs at the end of each line — the regex linters use to flag dirty whitespace.
Try it in the JS tester →Pattern
regexJS
[ \t]+$ (flags: gm)JavaScript / ECMAScript code
jsJavaScript
const re = new RegExp("[ \\t]+$", "gm");
const input = "good line\\nbad line \\nfine";
const matches = [...input.matchAll(re)];
console.log(matches.map(m => m[0]));Uses `String.prototype.matchAll` for global iteration (Node 12+ / all modern browsers).
How the pattern works
[ \t]+ matches one or more space or tab characters. $ with the m (multiline) flag anchors to the end of EACH line, not the whole string. The g flag iterates so a multi-line string surfaces every offending line. Pair with `replace(re, '')` to strip.
Examples
Input
good line\nbad line \nfineMatches
Input
tab here\tand more\t\tMatches
\t\t
Input
no trailing spaceNo match
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