$ cgrep src/*.cpp src/*.hpp --count
# Enter grep patterns starting with...
#   '+' for required patterns
#   '-' for rejected patterns
#   '=' for matched patterns
# Enter a blank line to submit.
> + <map> 
> + <vector>
> = #include
> 

src/grep_factory.hpp:4
src/output_strategy.hpp:5
src/parse_input.hpp:3

$ cgrep src/*.cpp src/*.hpp --count --pattern-file=patterns.txt
src/grep_factory.hpp:4
src/output_strategy.hpp:5
src/parse_input.hpp:3

+ <map> 
+ <vector>
= #include

$ cgrep src/*.cpp src/*.hpp --count --again
src/grep_factory.hpp:4
src/output_strategy.hpp:5
src/parse_input.hpp:3

[cgrep]
-------
Conditionally grep files using multiple
required(+), rejected(-) and matched(=) patterns.
Required and rejected patterns are resolved
before returning matches.
   
[usage]
-------
cgrep [-acEhilLn] [-p=pattern-file] [-o=output-file] [file ...]
   
[options]
---------
-a / --again
   Rerun previous query again.
-c / --count
   Count the number of matched lines in each file.
-E / --extended-regexp
   Sets pattern matching to egrep.
-h / --help
   Shows this page.
-i / --ignore-case
   Sets grep to ignore case when matching.
-l / --files-with-matches
   Lists all files with matched lines.
-L / --files-without-matches
   Lists all files without matched lines in search set.
-n / --line-number
   Each output line is preceded by its relative line number.
-o= / --output-file=
   Writes results to a file.
-p= / --pattern-file=
   Reads grep patterns from a file.