feat: C-l recenter cycle, M-g prefix goto-line, C-h k describe-key - #117
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Four small Emacs keybind gaps in one PR: C-l recenter cycle (middle->top->bottom, via a CFRECT flag + step counter in reposition); M-g -> goto-line (direct bind, since mg's one-prefix-per-element keymap makes a faithful M-g prefix disproportionate); C-x z repeat (last_command stored in mgwrap + a repeat cmd); C-h k -> describe-key (bind helpmap k to desckey). M-/ dabbrev and the M-g prefix form split into their own specs. Emacs 30.2 behavior verified. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01Pj1ZHaD7aNhVWJ69SFKJcp
Per review: full faithfulness. M-g becomes a real prefix via a self-referential gotomap (ESC re-enters itself so M-g M-g / M-g M-g M-g all reach goto-line) and splitting the metamap '['..'h' element into three sorted elements to give 'g' its own prefix slot. doscan confirms elements scan by ascending k_num and NULL k_funcp entries descend into k_prefmap. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01Pj1ZHaD7aNhVWJ69SFKJcp
4 tasks: C-h k -> desckey (cHa); M-g prefix (self-ref gotomap + split metamap '['..'h' into 3 sorted elements, KEYMAPE 8->10); C-l recenter cycle (CFRECT flag + w_frame 0/1/ntrows in reposition); C-x z repeat (expose last_command in mgwrap + repeat cmd + cXmap 'z', KEYMAPE 6->7). Each with a pty test. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01Pj1ZHaD7aNhVWJ69SFKJcp
…-h k describe-key Four Emacs keybind gaps (verified vs Emacs 30.2): - C-l cycles recenter middle->top->bottom (CFRECT flag + w_frame in reposition), was center-only. - M-g is a prefix map: M-g g and M-g M-g -> goto-line (new gotomap + metagmap; metamap '['..'h' element split into three sorted elements). NOT self-referential -- fixmap() walks prefix maps recursively at startup, so an ESC->self cycle overflowed the stack (SIGSEGV); metagmap breaks the cycle. - C-x z repeats the last command (last_command exposed from mgwrap + repeat cmd, press z to keep repeating), cXmap grown for 'z'. - C-h k -> describe-key-briefly (cHa 'k'), matching the Emacs reflex. macOS 326/326. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01Pj1ZHaD7aNhVWJ69SFKJcp
Whole-branch review found repeat() bypasses mgwrap/doin, so repeating selfinsert inserts the 'z' from C-x z (x -> 'xz', silent corruption) and repeating after undo reverses it (frozen rptcount). A correct repeat needs dispatch-context capture (key sequence + f/n + rptcount + ABORT) -- a separate feature, deferred to FM-REPEAT. Ship the three verified-correct keybinds: C-l recenter cycle, M-g prefix goto-line, C-h k describe-key. Spec updated (metagmap, not self-ref). macOS 325/325. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01Pj1ZHaD7aNhVWJ69SFKJcp
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01Pj1ZHaD7aNhVWJ69SFKJcp
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… deferral Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01Pj1ZHaD7aNhVWJ69SFKJcp
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feat: three Emacs keybinding gaps
Verified against Emacs 30.2:
C-lrecenter cycle — was center-only; now cycles middle → top → bottom on consecutive presses (recenter-top-bottom), via aCFRECTflag +w_frameinreposition.M-gprefix → goto-line —M-gwas unbound; now a real prefix map soM-g gandM-g M-gboth reachgoto-line(newgotomap/metagmap; the metamap'['..'h'element split into three sorted elements to give'g'its own prefix slot).C-h k→ describe-key — bound todescribe-key-briefly(mg has no doc strings), matching the reflex.Debugging + review notes
M-gattempt used a self-referentialgotomap(ESC→itself for infiniteM-g M-g M-g…) — it SIGSEGV'd at startup becausefixmap()walks prefix maps recursively (a cycle → stack overflow). Root-caused via an lldb backtrace, fixed with a separate acyclicmetagmap.C-x zrepeat, was dropped: the whole-branch review found it re-invoked the last command bypassingmgwrap/doin, so repeatingselfinsertinserted thezfromC-x z(x→xz, silent corruption) and repeating after undo reversed it. A correctrepeatneeds dispatch-context capture — deferred to its own spec,FM-REPEAT.Verification
macOS 325/325 · TSan zero races · Alpine/musl 325/325 · legacy plain-C clean (all plain C, ships in both builds).
Based on
neomg.🤖 Generated with Claude Code
https://claude.ai/code/session_01Pj1ZHaD7aNhVWJ69SFKJcp