different-ai/openwork · error · InterpreterRuntimeError

String.matchAll requires a regular expression with the globa

Error message

String.matchAll requires a regular expression with the global (g) flag: write /${pattern.source}/${pattern.flags}g, or use String.match for a single match.

What it means

String.matchAll requires a global regex; the host JS spec also throws a TypeError for non-global patterns here. The sandbox validates pattern.global after converting the argument via toHostRegex and throws with a message showing the fixed literal (flags + g) and suggesting String.match for a single match. Note this check only fires for patterns that survived toHostRegex without already erroring; the result is materialized as an array, not an iterator.

Source

Thrown at packages/codemode/src/interpreter/runtime.ts:453

        result = value.replace(str(0), str(1))
        break
      }
      result = value.replaceAll(str(0), str(1))
      break
    }
    case "match": {
      const pattern = toHostRegex(args[0], name, node)
      const matched = value.match(pattern)
      if (matched === null) return null
      // A global match is a plain array of matched strings; a non-global match carries
      // index/groups own properties, so bypass the copying data checkpoint to keep them.
      if (pattern.global) return boundedData(matched, "String.match result")
      return matchToValue(matched)
    }
    case "matchAll": {
      const pattern = toHostRegex(args[0], name, node, "g")
      if (!pattern.global) {
        throw new InterpreterRuntimeError(
          `String.matchAll requires a regular expression with the global (g) flag: write /${pattern.source}/${pattern.flags}g, or use String.match for a single match.`,
          node,
        )
      }
      // Materialized as an array (not an iterator); each entry is a match array with
      // index/groups own properties. Match count is bounded by the subject length.
      return Array.from(value.matchAll(pattern), matchToValue)
    }
    case "search": {
      result = value.search(toHostRegex(args[0], name, node))
      break
    }
    case "repeat": {
      const count = num(0)
      if (!Number.isFinite(count) || count < 0)
        throw new InterpreterRuntimeError("String.repeat expects a finite non-negative count.", node)
      result = value.repeat(count)
      break

View on GitHub (pinned to 2b7df46e8a)

Solutions

Add the g flag: str.matchAll(/ab/g)
Include 'g' when constructing dynamically: new RegExp(source, "g")
Use String.match(pattern) instead if only the first match is needed
For string search values, wrap them with an explicit global regex

Example fix

// before
for (const m of text.matchAll(/(\w+)=(\w+)/)) { ... }
// after
for (const m of text.matchAll(/(\w+)=(\w+)/g)) { ... }

Defensive patterns

Strategy: type-guard

Validate before calling

if (!(re instanceof RegExp && re.global)) throw new TypeError("matchAll needs a /g regex")
const matches = text.matchAll(re)

Type guard

const isGlobalRegex = (v) => v instanceof RegExp && v.global

Try / catch

try { out = [...text.matchAll(re)] } catch (e) { if (String(e.message).includes("global (g) flag")) out = text.match(re) !== null ? [text.match(re)] : []; else throw e }

Prevention

Never pass a regex without g to matchAll
Keep separate regex constants for match (single) vs matchAll (global)
Reset lastIndex concerns by using fresh global regexes per loop
Materialize the array (sandbox returns an array, not an iterator)

When it happens

Trigger: Calling str.matchAll(/ab/) without g; passing a regex built via new RegExp(src) with no flags; reusing a non-global regex shared with String.match or String.search; passing a string argument that toHostRegex converted into a non-global regex.

Common situations: Porting host code that iterated matchAll with a non-global regex and relied on the TypeError; generating regexes from user config where flags are omitted; switching from match to matchAll without adding the flag.

Related errors

AI-assisted analysis of different-ai/openwork@2b7df46e8a (2026-09-01). Data as JSON: /api/errors/6bf94c1c1190a873. Report an issue: GitHub.