Changelog

All notable changes to meme-clj will be documented in this file.

The format is based on Keep a Changelog.

[0.12.0] — 2026-04-01

Added

• Collapsar engine (meme.alpha.collapsar): self-contained declarative rewrite engine (584 LOC) with phases, pipelines, head analysis, verified termination, and tower collapse
• Collapsar meme↔clj pipeline (meme.alpha.collapsar.meme): meme-to-Clojure and Clojure-to-meme conversion expressed as collapsar rule phases and procedural phases
• Unified convert CLI: meme convert --pipeline classic|rewrite|collapsar selects the conversion pipeline; meme inspect --pipeline shows pipeline structure
• Unified convert module (meme.alpha.convert): single dispatch point for all three pipelines
• Comparative benchmark (benchmark_test.clj): benchmarks all three pipelines across 11 meme fixtures and 7,526 vendor forms from 7 real-world Clojure libraries
• Language platform: register! API for guest languages with custom preludes, rewrite rules, and parsers (meme.alpha.platform.registry)
• Term rewriter: bottom-up rewrite engine with ?x/??x pattern variables, cycle detection, and fixed-point iteration (meme.alpha.rewrite)
• Rewrite-based parser: alternative token→form path via tagged trees and rewrite rules (meme.alpha.rewrite.tree)
• Pipeline contracts: opt-in spec validation at stage boundaries (meme.alpha.pipeline.contract)
• LANGBOOK.md: language maker cookbook — patterns for building guest languages on the meme platform
• Superficie example: surface-syntax renderer reimplemented as a guest language (212 lines vs ~2000 original)

Fixed

• nil/true/false as call heads: the M-expression rule is purely syntactic — nil(1 2) → (nil 1 2). Any value can be a head. Previously these were rejected artificially.
• Tokenizer ns// symbols: clojure.core// now reads as one symbol (namespace clojure.core, name /). Previously split into two tokens.
• Rewrite emitter type gaps: BigDecimal M suffix, BigInt N suffix, ##NaN/##Inf/##-Inf, tagged literals, named chars (\newline etc.), pr-str fallback for UUID/Date
• Reader conditional preservation: all three pipelines now pass :read-cond :preserve during conversion, preserving #?(:clj ...) branches in output
• Prelude expansion: prelude forms are now expanded through step-expand-syntax-quotes before eval, matching the user-code path
• build-tree delimiter validation: build-tree now validates expected delimiters after #? and #:ns prefixes
• load-prelude docstring: corrected to reflect actual behavior (parse-only, not eval)
• README.md: fixed dead link to doc/development.md

[0.6.0-alpha] — 2026-03-30

Fixed

• defrecord-as-map bugs: MemeRaw, MemeSyntaxQuote, and other AST node defrecords satisfy (map? x), causing silent mishandling in expand-sq, normalize-bare-percent, find-percent-params, pp, and max-percent-n. All dispatch sites now guard with forms/raw?, forms/syntax-quote?, etc. before the (map? form) branch.
• #?@ splicing: #?@(:clj [2 3]) inside a collection now correctly splices elements ([1 #?@(:clj [2 3]) 4] produces [1 2 3 4], not [1 [2 3] 4]). Non-sequential splice values produce a clear error.
• Positive-sign BigInt/Ratio: +42N and +3/4 now parse correctly. BigInteger constructor rejects leading +; sign is now stripped before construction (matching hex/octal/radix branches).
• Literal head syntax: nil(x), true(x), false(x) are now valid meme syntax, producing the lists (nil x), (true x), (false x). The syntactic rule f(args) → (f args) applies uniformly regardless of head type.
• Nested syntax-quote semantics: x `` now correctly produces double-quoting (code that generates the inner expansion), matching Clojure's behavior. Previously the inner expansion was returned directly, losing one nesting level.

Changed

• Expander extracted: Syntax-quote expansion (expand-sq, expand-syntax-quotes, expand-forms) moved from meme.alpha.parse.reader to new meme.alpha.parse.expander namespace.
• Shared utilities: Metadata exclusion key set (strip-internal-meta) and percent-param-type extracted to meme.alpha.forms to prevent drift between reader and printer.
• CI deploy gate: ClojureScript tests now required before deployment (added test-cljs to deploy job dependencies).

[0.5.0-alpha] — 2025-03-30

Initial public alpha release.

Added

• Three-stage pipeline: scan (tokenizer) -> group -> parse (reader)
• Printer and pretty-printer (width-aware, comment-preserving)
• Full Clojure syntax support: all special forms, reader macros, dispatch forms
• Syntactic transparency via :meme/sugar metadata preservation
• Syntax-quote preserved as AST node (MemeSyntaxQuote), expanded before eval
• Raw value wrapper (MemeRaw) for numbers/chars/strings with alternate notation
• :read-cond :preserve option for lossless reader conditional roundtrips
• REPL with multi-line input and :incomplete continuation protocol
• CLI (run, repl, convert, format) — self-hosted in .meme
• Cross-platform support: JVM, Babashka, ClojureScript
• Generative property-based tests (14 properties, 200-300 samples each)
• Vendor roundtrip tests against 7 real-world Clojure libraries
• Dogfood tests with clj-kondo semantic equivalence verification
• Clojars deployment via CI on version tags