docs: add comments for closure

[xieyuschen]

No description provided.

[github-actions]

Benchmark for 232b1d4

Click to view benchmark

Test	Base	PR	%
allocation bench/malloc benchmark small objects	34.2±10.85ns	35.2±10.91ns	+2.92%
allocation bench/singlethread gc alloc benchmark small objects	11.5±0.21ns	11.5±0.18ns	0.00%
multithreads(4) gc benchmark--65535 small objects(per thread)	1762.2±202.51µs	1839.9±349.62µs	+4.41%
plimmixgc/multi-thread gc stress benchmark small objects	914.8±13.23ms	976.2±49.12ms	+6.71%
plimmixgc/singlethread gc stress benchmark small objects	580.1±10.94ms	578.3±11.73ms	-0.31%
singlethread gc benchmark--65535 small objects	750.0±4.52µs	754.1±4.90µs	+0.55%

[github-actions]

Benchmark for e9f5983

Click to view benchmark

Test	Base	PR	%
allocation bench/malloc benchmark small objects	33.9±9.34ns	34.1±10.56ns	+0.59%
allocation bench/singlethread gc alloc benchmark small objects	11.5±0.23ns	11.9±1.80ns	+3.48%
multithreads(4) gc benchmark--65535 small objects(per thread)	1519.6±99.94µs	1638.5±354.45µs	+7.82%
plimmixgc/multi-thread gc stress benchmark small objects	932.5±22.29ms	908.1±23.66ms	-2.62%
plimmixgc/singlethread gc stress benchmark small objects	592.2±40.99ms	572.9±11.10ms	-3.26%
singlethread gc benchmark--65535 small objects	772.8±5.84µs	796.2±3.25µs	+3.03%

[github-actions]

Benchmark for cda6fd3

Click to view benchmark

Test	Base	PR	%
allocation bench/malloc benchmark small objects	34.4±10.40ns	34.9±12.23ns	+1.45%
allocation bench/singlethread gc alloc benchmark small objects	12.0±0.28ns	11.5±0.23ns	-4.17%
multithreads(4) gc benchmark--65535 small objects(per thread)	1561.9±235.07µs	1512.4±69.59µs	-3.17%
plimmixgc/multi-thread gc stress benchmark small objects	912.5±19.58ms	992.0±48.72ms	+8.71%
plimmixgc/singlethread gc stress benchmark small objects	585.8±11.34ms	586.2±11.92ms	+0.07%
singlethread gc benchmark--65535 small objects	755.0±11.48µs	758.4±9.91µs	+0.45%

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 86.60%. Comparing base (336be9c) to head (f0faaa1).

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #404      +/-   ##
==========================================
+ Coverage   86.57%   86.60%   +0.03%     
==========================================
  Files         111      111              
  Lines       26433    26473      +40     
==========================================
+ Hits        22884    22928      +44     
+ Misses       3549     3545       -4     

Files	Coverage Δ
src/ast/builder/llvmbuilder.rs	93.29% <100.00%> (+0.01%)	⬆️
src/ast/ctx.rs	94.69% <100.00%> (ø)
src/ast/macros.rs	92.59% <ø> (ø)
src/ast/node/function.rs	91.34% <100.00%> (+0.23%)	⬆️
src/ast/node/mod.rs	83.94% <ø> (ø)
src/ast/node/statement.rs	80.74% <100.00%> (+0.07%)	⬆️
src/ast/pltype.rs	87.72% <ø> (ø)

... and 1 file with indirect coverage changes

[github-actions]

Benchmark for ddf03ec

Click to view benchmark

Test	Base	PR	%
allocation bench/malloc benchmark small objects	33.1±6.40ns	34.5±13.74ns	+4.23%
allocation bench/singlethread gc alloc benchmark small objects	11.3±0.24ns	11.3±0.47ns	0.00%
multithreads(4) gc benchmark--65535 small objects(per thread)	1559.6±80.17µs	1483.8±69.76µs	-4.86%
plimmixgc/multi-thread gc stress benchmark small objects	968.6±30.20ms	978.5±71.88ms	+1.02%
plimmixgc/singlethread gc stress benchmark small objects	576.7±11.20ms	577.7±10.49ms	+0.17%
singlethread gc benchmark--65535 small objects	761.7±16.96µs	727.6±13.76µs	-4.48%