This script parses a C or C++ header and generates an implementation file based on the function prototypes found within. It is designed to take one class or namespace at a time, so the scope resolution is based off of the header file's name.

ParseHeader.py

#!/usr/bin/env python3

#This program parses C/C++ header files and outputs a corresponding
#implementation file. It uses a regular expression to isolate function
#prototypes and converts them to implementations.
#This program is designed to take a single class or namespace as input.

import sys
import os
import re

def main():
    try:
        header = open(sys.argv[1], 'r')
    except IndexError:
        header = open(input('Enter the path to a header file: '), 'r')
    os.chdir(os.path.dirname(header.name))
    headerName = re.sub('\.\w+$', '', os.path.basename(header.name))
    headerContent = header.read()
    scopeResolve = input('Do you want the function names to be prefixed with a scope [y/n]? ')
    if re.search('(y|Y)', scopeResolve):
        className = ''
    else:
        className = headerName
    del scopeResolve
    source = open(headerName + '.cc', 'w')
    source.write('#include "' + headerName + '.hh"\n')
    source.write('using namespace std;\n\n')
    source.write(parse(headerContent, className))
    header.close()
    source.close()

def parse(header, scope):
    if scope != '':
        scope += '::'
    prototypeMatch = re.compile('[^\s]([\w=+-/*%<>:, ]+)[^\s]\(.*\)([\w,: ]*)?;')
    headingMatch = re.compile('(\w+\()')
    out = ''
    for match in prototypeMatch.finditer(header):
        #Make a new string holding the prototype
        code = header[match.start() : match.end()]
        #Insert scope resolution
        code = headingMatch.sub(scope + r'\1', code)
        #Replace the semicolon
        code = re.sub(r';', ' {\n\n}\n\n', code)
        out += code
    return out

main()