GitHub Actions Expression in JS
Match `${{ expression }}` interpolations used in GitHub Actions workflow YAML.
Try it in the JS tester →Pattern
regexJS
\$\{\{\s*([^}]+?)\s*\}\} (flags: g)JavaScript / ECMAScript code
jsJavaScript
const re = new RegExp("\\$\\{\\{\\s*([^}]+?)\\s*\\}\\}", "g");
const input = "if: ${{ github.actor == 'octocat' }}";
const matches = [...input.matchAll(re)];
console.log(matches.map(m => m[0]));Uses `String.prototype.matchAll` for global iteration (Node 12+ / all modern browsers).
How the pattern works
\$\{\{ matches the literal `${{`. \s*([^}]+?)\s* lazily captures the inner expression (with surrounding whitespace stripped). \}\} matches the closing `}}`. The lazy quantifier prevents accidentally consuming through to a later `}}` in the same line.
Examples
Input
if: ${{ github.actor == 'octocat' }}Matches
${{ github.actor == 'octocat' }}
Input
run: echo ${{ secrets.NPM_TOKEN }} | npm publishMatches
${{ secrets.NPM_TOKEN }}
Input
no expressionsNo match
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