E-PURE-001 was
retired 2026-07-16 and is no longer emitted by
the compiler. It is superseded by the
E-FN-001…009 family, which
SPEC §33.6 defines as specialized subcategories of it. The
pure modifier is deprecated
language-wide — use fn.
This page is kept because older build output and existing code
still reference the old code.
E-PURE-001
pure-marked function performs a non-pure operation (write, IO, mutation).
Per-code reference page queued for the Day-30 build-out.
The full template (what it means · minimal reproducer · how to fix · related · specification) is being rolled out across every error code the compiler can emit. Until this page lands, the catalogue row in SPEC §34 is authoritative.