Editor tooling

Pop-11 Editor Tooling

A tree-sitter grammar for Pop-11 that parses 95.2% of the full 270k-line Poplog tree, plus a Zed extension built on it — highlighting, outline, folding, and brackets for a language whose syntax programs may extend at compile time.

Source on GitHub Read launch story

What it is

Two repositories that give Pop-11 sources a modern editing experience:

  • tree-sitter-pop11 — the grammar, with highlight, fold and textobject queries.
  • zed-pop11 — the Zed extension built on it: highlighting, outline symbols, folding, brackets and comments for .p, .ph and .pop11 files. Available from the Zed extension registry.

The hard part

Pop-11’s syntax is user-extensible — a program can define new syntax words at compile time — so no static grammar can ever be complete. The design goal was therefore graceful degradation, not completeness: parse the stable core faithfully and let everything else fall back to a flat item “soup” rather than derailing the file.

The core it handles covers comments (including nesting /* … */), strings and word literals in their closed, """ and unclosed "ml] forms, character constants in every historical spelling, radix numbers, the full range of define/enddefine shapes, the closed set of block syntax words and their end… closers, declarations and uses forms, exload blocks, vedset key maps, the #_IF compile-time directives, and Pop-11’s quoting semantics — where [ … ] and { … } make their contents data and % … % switches back to evaluation.

Measured, not asserted

The grammar is validated against the complete Poplog tree — 1,805 files, 270,000 lines spanning 1985 to 2026, including the syspop system dialect and the internals of the Lisp, Prolog and ML subsystems. 95.2% of files parse without errors; the user-facing library corpus and every modern library parse clean.

Status

Active. v0.1 — phase P1 of the Poplog editor-bindings plan. The Pop-11 LSP server (real-compiler diagnostics, HELP hover, dictionary completion) already ships in the Poplog repo; wiring it into Zed needs extension WASM and is the planned follow-up.

One documented caveat: .p is contested — Pascal, Gnuplot and OpenEdge claim it too, and Zed has no content sniffing. The extension takes .p; projects where that is wrong override it in .zed/settings.json.