cw - Count Words
wc clone in Rust.
-% cw --help cw 0.5.0 Thomas Hurst <firstname.lastname@example.org> Count Words - word, line, character and byte count USAGE: cw [FLAGS] [OPTIONS] [input]... FLAGS: -c, --bytes Count bytes -m, --chars Count UTF-8 characters instead of bytes -h, --help Prints help information -l, --lines Count lines -L, --max-line-length Count bytes (default) or characters (-m) of the longest line -V, --version Prints version information -w, --words Count words OPTIONS: --files0-from <files0_from> Read input from the NUL-terminated list of filenames in the given file. --files-from <files_from> Read input from the newline-terminated list of filenames in the given file. --threads <threads> Number of counting threads to spawn [default: 1] ARGS: <input>... Input files -% cw Dickens_Charles_Pickwick_Papers.xml 3449440 51715840 341152640 Dickens_Charles_Pickwick_Papers.xml
Counts of multiple files may be accelerated by use of the
'xargs <files cw --threads=12' ran 2.01 ± 0.03 times faster than 'xargs <files cw --threads=4' 7.07 ± 0.09 times faster than 'xargs <files cw' 11.55 ± 0.15 times faster than 'xargs <files wc' 17.31 ± 0.23 times faster than 'xargs <files gwc'
Line counts are optimized using the
'cw -l Dickens_Charles_Pickwick_Papers.xml' ran 3.44 ± 0.04 times faster than 'wc -l Dickens_Charles_Pickwick_Papers.xml' 4.17 ± 0.05 times faster than 'gwc -l Dickens_Charles_Pickwick_Papers.xml'
Line counts with line length are optimized using the
'cw -lL Dickens_Charles_Pickwick_Papers.xml' ran 1.73 ± 0.01 times faster than 'wc -lL Dickens_Charles_Pickwick_Papers.xml' 15.07 ± 0.07 times faster than 'gwc -lL Dickens_Charles_Pickwick_Papers.xml'
-m cw only operates on bytes, and it never cares about your locale.
'cw Dickens_Charles_Pickwick_Papers.xml' ran 1.45 ± 0.01 times faster than 'wc Dickens_Charles_Pickwick_Papers.xml' 2.05 ± 0.00 times faster than 'gwc Dickens_Charles_Pickwick_Papers.xml'
-m enables UTF-8 processing, with a fast-path for just character length, again
'cw -m Dickens_Charles_Pickwick_Papers.xml' ran 30.21 ± 0.39 times faster than 'gwc -m Dickens_Charles_Pickwick_Papers.xml' 70.36 ± 0.91 times faster than 'wc -m Dickens_Charles_Pickwick_Papers.xml'
'cw -m test-utf-8.html' ran 84.74 ± 1.12 times faster than 'wc -m test-utf-8.html' 124.21 ± 1.64 times faster than 'gwc -m test-utf-8.html'
And another path for character and line length:
'cw -mlL Dickens_Charles_Pickwick_Papers.xml' ran 3.88 ± 0.01 times faster than 'gwc -mlL Dickens_Charles_Pickwick_Papers.xml' 9.05 ± 0.02 times faster than 'wc -mlL Dickens_Charles_Pickwick_Papers.xml'
'cw -mlL test-utf-8.html' ran 9.42 ± 0.01 times faster than 'wc -mlL test-utf-8.html' 18.95 ± 0.03 times faster than 'gwc -mlL test-utf-8.html'
And a slow path for everything else:
'cw -mLlw Dickens_Charles_Pickwick_Papers.xml' ran 1.35 ± 0.00 times faster than 'gwc -mLlw Dickens_Charles_Pickwick_Papers.xml' 3.15 ± 0.00 times faster than 'wc -mLlw Dickens_Charles_Pickwick_Papers.xml'
These tests are on FreeBSD 12 on a 2.1GHz Westmere Xeon.
gwc is from GNU
coreutils 8.30 - note its performance here is rather pessimised in some areas by
FreeBSD's rather weak
memchr implementation. YMMV.
For best results build with:
cargo build --release --features runtime-dispatch-simd
This enables SIMD optimizations for line and character counting. It has no effect if you count anything else.
- Test suite.
- Factor internals out into a library. (#1)
- Improve multibyte support.
- Possibly implement locale.
- Replace clap/structopt with something lighter.
uwc focuses on following Unicode rules as precisely as possible, taking into account less-common newlines, counting graphemes as well as codepoints, and following Unicode word-boundary rules precisely.
The cost of this is currently a great deal of performance, with counts on my benchmark file taking over a minute.
cw was originally called rwc until I noticed this existed. It's quite old and doesn't appear to compile.
A little library that only does plain newline counting, along with a binary
lc. Version 0.2 will use the same algorithm as