This answer is extended from @Adam Merberg's answer.
Modifications:
- The original snippet neglect that sometimes
\makeatletter \makeatother block need the % at the end of some lines. Removing those % will result in compilation failure.
For example:
\makeatletter
\def\alloc@#1#2#3#4#5%
{\ifnum\count1#1<#4% make sure there's still room
\allocationnumber\count1#1
\global\advance\count1#1\@ne
\global#3#5\allocationnumber
\wlog{\string#5=\string#2\the\allocationnumber}%
\else\ifnum#1<6
\def\etex@dummy@definition{}% <-- code added
\begingroup \escapechar\m@ne
\expandafter\alloc@@\expandafter{\string#2}#5%
\else\errmessage{No room for a new #2}\fi\fi
}
\makeatother
The % at the end of the 2nd line must be preserved.
- The original snippet will trim the ending
\n if there is a line comment, which consequently merge the next line to current line.
For example,
\usepackage{foo} % foo package
\usepackage{bar}
\usepackage{baz}
will result in
\usepackage{foo} \usepackage{bar}
\usepackage{baz}
The modified snippet:
import ply.lex, argparse, io
# modified from https://gist.github.com/amerberg/a273ca1e579ab573b499
#Usage
# python stripcomments.py input.tex > output.tex
# python stripcomments.py input.tex -e encoding > output.tex
# Modification:
# 1. Preserve "\n" at the end of line comment
# 2. For \makeatletter \makeatother block, Preserve "%"
# if it is actually a comment, and trim the line
# while preserve the "\n" at the end of the line.
# That is because remove the % some time will result in
# compilation failure.
def strip_comments(source):
tokens = (
'PERCENT', 'BEGINCOMMENT', 'ENDCOMMENT',
'BACKSLASH', 'CHAR', 'BEGINVERBATIM',
'ENDVERBATIM', 'NEWLINE', 'ESCPCT',
'MAKEATLETTER', 'MAKEATOTHER',
)
states = (
('makeatblock', 'exclusive'),
('makeatlinecomment', 'exclusive'),
('linecomment', 'exclusive'),
('commentenv', 'exclusive'),
('verbatim', 'exclusive')
)
# Deal with escaped backslashes, so we don't
# think they're escaping %
def t_BACKSLASH(t):
r"\\\\"
return t
# Leaving all % in makeatblock
def t_MAKEATLETTER(t):
r"\\makeatletter"
t.lexer.begin("makeatblock")
return t
# One-line comments
def t_PERCENT(t):
r"\%"
t.lexer.begin("linecomment")
# Escaped percent signs
def t_ESCPCT(t):
r"\\\%"
return t
# Comment environment, as defined by verbatim package
def t_BEGINCOMMENT(t):
r"\\begin\s*{\s*comment\s*}"
t.lexer.begin("commentenv")
#Verbatim environment (different treatment of comments within)
def t_BEGINVERBATIM(t):
r"\\begin\s*{\s*verbatim\s*}"
t.lexer.begin("verbatim")
return t
#Any other character in initial state we leave alone
def t_CHAR(t):
r"."
return t
def t_NEWLINE(t):
r"\n"
return t
# End comment environment
def t_commentenv_ENDCOMMENT(t):
r"\\end\s*{\s*comment\s*}"
#Anything after \end{comment} on a line is ignored!
t.lexer.begin('linecomment')
# Ignore comments of comment environment
def t_commentenv_CHAR(t):
r"."
pass
def t_commentenv_NEWLINE(t):
r"\n"
pass
#End of verbatim environment
def t_verbatim_ENDVERBATIM(t):
r"\\end\s*{\s*verbatim\s*}"
t.lexer.begin('INITIAL')
return t
#Leave contents of verbatim environment alone
def t_verbatim_CHAR(t):
r"."
return t
def t_verbatim_NEWLINE(t):
r"\n"
return t
#End a % comment when we get to a new line
def t_linecomment_ENDCOMMENT(t):
r"\n"
t.lexer.begin("INITIAL")
# Newline at the end of a line comment is presevered.
return t
#Ignore anything after a % on a line
def t_linecomment_CHAR(t):
r"."
pass
def t_makeatblock_MAKEATOTHER(t):
r"\\makeatother"
t.lexer.begin('INITIAL')
return t
def t_makeatblock_BACKSLASH(t):
r"\\\\"
return t
# Escaped percent signs in makeatblock
def t_makeatblock_ESCPCT(t):
r"\\\%"
return t
# presever % in makeatblock
def t_makeatblock_PERCENT(t):
r"\%"
t.lexer.begin("makeatlinecomment")
return t
def t_makeatlinecomment_NEWLINE(t):
r"\n"
t.lexer.begin('makeatblock')
return t
# Leave contents of makeatblock alone
def t_makeatblock_CHAR(t):
r"."
return t
def t_makeatblock_NEWLINE(t):
r"\n"
return t
# For bad characters, we just skip over it
def t_ANY_error(t):
t.lexer.skip(1)
lexer = ply.lex.lex()
lexer.input(source)
return u"".join([tok.value for tok in lexer])
def main():
parser = argparse.ArgumentParser()
parser.add_argument('filename', help = 'the file to strip comments from')
parser.add_argument('--encoding', '-e', default='utf-8')
args = parser.parse_args()
with io.open(args.filename, encoding=args.encoding) as f:
source = f.read()
print(strip_comments(source))
if __name__ == '__main__':
main()
The Gist for the code is here.
verbatimpackage.%blabla ..