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README.md

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+# BPEG
+
+BPEG is a parsing expression grammar tool for the command line.
+It's written in pure C with no dependencies.
+
+## Usage
+`bpeg [flags] <pattern> [<input files>...]`
+
+### Flags
+* `-h` `--help` print the usage and quit
+* `-v` `--verbose` print verbose debugging info
+* `-d` `--define <name>=<def>` define a grammar rule
+* `-D` `--define-string <name>=<def>` define a grammar rule (string-pattern)
+* `-p` `--pattern <pat>` provide a pattern (equivalent to bpeg '
+* `-P` `--pattern-string <pat>` provide a string pattern (equivalent to bpeg '<pat>', but may be useful if '<pat>' begins with a '-')
+* `-r` `--replace <replacement>`   replace the input pattern with the given replacement
+* `-m` `--mode <mode>` set the behavior mode (defult: find-all)
+* `-g` `--grammar <grammar file>`  use the specified file as a grammar
+
+See `man ./bpeg.1` for more details.
+
+## BPEG Patterns
+BPEG patterns are a mixture of Parsing Expression Grammar and Regular
+Expression syntax, with a preference for prefix operators instead of
+suffix operators.
+
+See `man ./bpeg.1` for more details.
+
+## License
+BPEG is provided under the MIT license with the Commons Clause (see
+[LICENSE](LICENSE) for details).