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0.*
===
0.82
----
**Unreleased**
62/76 GNU find features supported.
- Rework optimization levels
- `-O1` (logical simplification):
- Constant propagation (`! -false <==> -true`, `! -true <==> -false`)
- Double negation (`! ! X <==> X`)
- Conjunction elimination:
- `-true -a X <==> X`
- `X -a -true <==> X`
- Disjunctive syllogism:
- `-false -o X <==> X`
- `X -o -false <==> X`
- Short-circuiting:
- `-false -a X <==> -false`
- `-true -o X <==> -true`
- De Morgan's laws (**new**):
- `( ! X -a ! Y ) <==> ! ( X -o Y )`
- `( ! X -o ! Y ) <==> ! ( X -a Y )`
- `! ( X -a ! Y ) <==> ( ! X -o Y )`
- `! ( X -o ! Y ) <==> ( ! X -a Y )`
- `! ( ! X -a Y ) <==> ( X -o ! Y )`
- `! ( ! X -o Y ) <==> ( X -a ! Y )`
- Unused result (**new**): `! X , Y <==> X , Y`
- `-O2` (purity):
- (These optimizations take the purity of predicates into account, allowing side-effect-free tests like `-name` or `-type` to be moved or removed)
- `PURE -a -false <==> -false`
- `PURE -o -true <==> -true`
- `PURE , X <==> X`
- Top-level unused result (**new**): `X (-a|-o|,) PURE <==> X`
- `-O3` (cost-based, **default**):
- Re-order tests to reduce the expected cost (TODO)
- `-O4` (aggressive):
- (These are very aggressive optimizations that may have surprising effects on warning/error messages and runtime, but still should not affect the resulting output)
- Change top-level expressions with no actions to `-false` (**new**):
- For example, `bfs -O4 -true -o -print` becomes `-false`, because `-print` is unreachable
- Skip the entire traversal if the top-level expression is `-false`
- `bfs -O4 -false` (or anything that optimizes to `-false`) will exit immediately
- This may cause messages about non-existent files, symbolic link cycles, etc. to be skipped
- `-Ofast`:
- Always the highest level, currently the same as `-O4`
- Color files with multiple hard links correctly
- Treat `-`, `)`, and `,` as paths when required to by POSIX
- `)` and `,` are only supported before the expression begins
- Implement `-D opt`
- Implement `-fprint`
- Implement `-fprint0`
0.79
----
**May 27, 2016**
60/76 GNU find features supported.
- Remove an errant debug `printf()` from `-used`
- Implement the `{} ;` variants of `-exec`, `-execdir`, `-ok`, and `-okdir`
0.74
----
**March 12, 2016**
56/76 GNU find features supported.
- Color broken symlinks correctly
- Fix https://github.com/tavianator/bfs/issues/7
- Fix `-daystart`'s rounding of midnight
- Implement (most of) `-newerXY`
- Implement `-used`
- Implement `-size`
0.70
----
**February 23, 2016**
53/76 GNU find features supported.
- New `make install` and `make uninstall` targets
- Squelch non-positional warnings for `-follow`
- Reduce memory footprint by as much as 64% by closing `DIR*`s earlier
- Speed up `bfs` by ~5% by using a better FD cache eviction policy
- Fix infinite recursion when evaluating `! expr`
- Optimize unused pure expressions (e.g. `-empty -a -false`)
- Optimize double-negation (e.g. `! ! -name foo`)
- Implement `-D stat` and `-D tree`
- Implement `-O`
0.67
----
**February 14, 2016**
Initial release.
51/76 GNU find features supported.
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