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In LaTeX, % can be used for single-line comments. For multi-line comments, the following command is available in the verbatim package.

Commented code

But is there a simple command like /* code */ in C?

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Related/duplicate: Commenting out large sections – Qrrbrbirlbel Dec 18 '12 at 7:22
Also see: Block comments in TeX – Aditya Dec 18 '12 at 8:03

Following the C code paradigm, where one can use the preprocessor directives

#if 0
junk code

something similar can be done in TeX (and descendants):

I don't want this to happen

The commented parts can be easily activated by replacing \iffalse with \iftrue.

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See the TeX FAQ on why \iffalse can fail in unexpected ways. – Aditya Dec 18 '12 at 8:04
@Aditya: thanks for the link, I wasn't aware of these problems! – guillem Dec 18 '12 at 8:35

No, but you can define something close:



\/* This is a test
    and this is another

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Can you make \* multiline comments *\ ? – kiss my armpit Dec 17 '12 at 7:01
@GarbageCollector You can but then it means changing the catcode of the backtick to make it active and would cause a lot of grief in other areas. Ah! did not see your edit ... changing catcode of slash will give you same headaches. – Yiannis Lazarides Dec 17 '12 at 7:03
@YiannisLazarides: Of course, this definition cannot be nested. With LuaTeX it is possible to have multiline comments without any catcode jugglery. See Block comments in TeX for an example. – Aditya Dec 18 '12 at 8:06
It redefines \* and requires a space after the closing delimiter but, \def\*#1*\ {} works I think. – Scott H. Dec 22 '12 at 21:05

Here's a poor man's version of the answer linked by Aditya above. It doesn't require ConTeXt but it does need to be compiled with LuaTeX. With it you can use C style comments: /*comment*/. A potential downside is that it "works" even in a verbatim environment. It works in all situations I can think of.

This input:

enter image description here

Gives this output:

enter image description here




commenting = false
local gsub = string.gsub

local opencomm = "%/%*(.*)"
local closecomm = "(.-)%*%/"

function comment(s)
    if not commenting then
        s = gsub(s,opencomm,
                commenting = true
                s1 =  gsub(s1,closecomm,function(s2) commenting = false return "" end,1)
                  if commenting then return "" else
                      return comment(s1)
        s = gsub(s,"(.+)",
                s3 =  gsub(s,closecomm,function(s4) commenting = false return "" end,1)
                    if commenting then return "%" else
                        return comment(s3)
    return s

luatexbase.add_to_callback('process_input_buffer', comment, 'comment')


1 /*HIDDEN*/ 2





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I think the most straightforward way to do this is to use a TeX editor. TeXnicCenter for instance offers to comment and uncomment marked blocks by ctrl+q and ctrl+w. This simply adds a '%' at the respective lines. This further grays out commented section, which is not the case with scripted solutions.

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you can't have inline comments as such for example 2 /* HIDDEN HIDDEN HIDDEN */ 3 – percusse Nov 27 '13 at 21:18
This is true of course. A scripted version also lets hide/show comments by a simple compile flag, which can be great in drafting or reviewing work. – Thomas Ortner Nov 27 '13 at 21:46

Short: put \directlua{-- before the block and a single } after the block when compiling with Lua(La)TeX.

Long: this is a "bug" of LuaTeX turned into a feature, or what make programmers happy. Putting a double hyphen in front of a text in Lua means a single-line comment; however, since TeX strips newlines from Lua code, this appears as a single-line chunk to Lua and so all the chunk gets commented.

Not tested, but I think you could alias that as

\newcommand{\multlinecomment}[1]{\directlua{-- #1}}

and then enclose your comment as in

  My multiline
  with Lorem ipsum.
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protected by Community Jul 5 '15 at 16:24

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