Sweep 19 Sep 2026 · 02:36Z Build v2.1.278 500 read Stable v2.1.267 Latest v2.1.278 Next v2.1.278 Feeds RSS JSON llms.txt Unofficial
Claude Code v2.1.269 ·

CEL comprehension macro bug fix: error checks were on the wrong variable

Fixed a bug where CEL comprehension expressions could silently swallow evaluation errors

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KindBug Fixesin v2.1.269,
You'll notice

Fixed a bug where CEL comprehension expressions could silently swallow evaluation errors

What

Claude Code uses CEL (Common Expression Language) internally to evaluate list and map comprehensions, the kind of expression used to loop over or filter a collection. Several checks that were supposed to detect evaluation errors were accidentally checking the wrong variable, a leftover from earlier code minification, instead of the value that had actually just been computed. This has been fixed so the error checks now test the right value.

Why

Before this fix, an error occurring inside a for- or filter-style comprehension could go undetected and be treated as if evaluation had succeeded, potentially producing incorrect results (such as a type mismatch between an iterable and a non-iterable) without surfacing the underlying error.

See this entry in the whole of v2.1.269 →