feat(manifest): bare OS-alias sugar for [target.*] conditional tables (v0.0.80)#192
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… (v0.0.80) [target.linux.dependencies] / [target.windows.build] now work as concise sugar for [target.'cfg(linux)'...] — dropping the cfg() wrapper and its mandatory TOML quotes for the common single-OS case. The bare aliases windows/linux/macos/unix are never valid triples, so there's no ambiguity with the exact-triple namespace. One evaluator branch in cfgpred::matches() (the parser already routes deps/build for any [target.<key>] into conditionalConfigs); evaluation stays target-resolved, identical to cfg(). Backward-compatible: cfg(...) and exact triples unchanged. toolchain/linkage remain exact-triple only (documented). - src/build/prepare.cppm: cfgpred::matches() bare-alias branch - tests/e2e/91_target_bare_alias.sh: bare alias works + parity with cfg(), host-aware - docs/05-mcpp-toml.md (+zh): new §2.7.1 documenting all three [target.*] forms (the L1 conditional config was previously undocumented in the user guide) - design doc; version -> 0.0.80
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What
Makes the common platform-conditional case concise.
[target.linux.dependencies]/[target.windows.build]now work as sugar for[target.'cfg(linux)'...]— dropping thecfg(...)wrapper and its TOML-mandated quotes.Why it's unambiguous
A mcpp triple is always
<arch>-<os>[-<env>]; the bare aliaseswindows/linux/macos/unixare never valid triples, so[target.linux]can only meancfg(linux)— no collision with the exact-triple namespace ([target.x86_64-linux-musl]). A small, deliberate divergence from Cargo (which always requirescfg()/triple), justified by removing quote-noise from the 90% case.Implementation
The parser already routes
build/dependenciesfor every[target.<key>]into aConditionalConfig{predicate=<key>}, so the only gap was evaluation. One branch incfgpred::matches()evaluates a bare alias as the cfg bareword. Evaluation stays target-resolved (identical tocfg());cfg(...)and exact triples unchanged → backward-compatible.toolchain/linkageremain exact-triple only (documented boundary).Files
src/build/prepare.cppm—cfgpred::matches()bare-alias branch.tests/e2e/91_target_bare_alias.sh— bare alias works and equalscfg()per-OS (parity), host-aware (validates on linux/macOS/windows).docs/05-mcpp-toml.md(+zh) — new §2.7.1 documenting all three[target.*]forms (the L1 conditional config was previously undocumented in the user guide)..agents/docs/2026-06-30-target-bare-alias-sugar-design.md; version → 0.0.80.Verified locally (0.0.80)
91_target_bare_aliaspasses;85(cfg flags) +86(cfg deps) regress clean; a macOS-gated bogus dep is correctly skipped on a Linux host via the bare alias.🤖 Generated with Claude Code