Comments is an actively used design pattern. Comments generally refer to free text ignored by the compiler that is not part of the language grammar.

?Years Old

Languages without Comments include json

Languages with Comments include acl2, ada, apex, apl, applescript, asymptote, autohotkey, autoit, awk, babel, ballerina, basic, befunge, c, chapel, chuck, clean, clojure, cobol, coffeescript, coldfusion, common-lisp, cpp, d, dart, dedukti, delphi, dylan, e, ecl, edn, eiffel, elixir, elm, erlang, euphoria, f-sharp, factor, falcon, false, fancy, fish, fml-lang, forth, fortran, freebasic, frink, futhark, gambas, gap, genie, go, graphql-sdl, gw-basic, haskell, haxe, idl, ini, io, j, java, javascript, jcl, joy, julia, k, konsolscript, kotlin, lasso, latex, lily, lilypond, lingo, livecode, logo, logtalk, lotusscript, lua, m4, maple, matlab, maxima, maxscript, metafont, mirah, modula-2, modula-3, monte, moo, neko, nemerle, nesl, netrexx, newlisp, nim, nsis, oberon-2, ocaml, octave, openscad, oz, pascal, perl, php, picolisp, pike, postscript, powershell, processing, prolog, purebasic, purescript, python, r, racket, rebol, rexx, ring, rlab, ruby, rust, sas, sather, scala, scheme, scilab, seed7, setl, simula, smalltalk, snobol4, sql, squirrel, stata, swift, tcl, turbo-pascal, txr, unlambda, vba, vbscript, verilog, vhdl, xojo, xpl0, xquery, xslt

Example from ballerina:

// A comment

Example from basic:

REM This BASIC program shows the use of the PRINT and GOTO Statements.

Example from c:

/* hello world */
// hi

Example from dart:

// Hi
/* Assume address is not null. */

Example from dedukti:

(; This is a comment ;)

Example from elixir:

# this is a comment

Example from erlang:

% hello world program

Example from fml-lang:

# This is a line comment

This is a block comment

Example from fortran:

C Lines that begin with 'C' (in the first or 'comment' column) are comments

Example from go:

// This is a comment

Example from haskell:

 -- a single line comment
 {- A multiline comment
    which can continue for many lines

Example from ini:

# a '#' or ';' character indicates
; a comment

Example from julia:

# This is a comment

Example from matlab:

% This is a comment

Example from ocaml:

(* This is a single-line comment. *)
(* This is a
 * multi-line
 * comment.

Example from perl:

# This is a comment in perl
=begin comment
This is all part of multiline comment.
You can use as many lines as you like
These comments will be ignored by the 
compiler until the next =cut is encountered.

Example from python:

# This is a comment

Example from ruby:

# This is a single line comment.

Example from rust:

// a comment

Example from turbo-pascal:

{ within pairs of braces }
(* left parenthesis/asterisk and asterisk/right parenthesis pairs *)
// preceded by two forward slashes

Last updated February 18th, 2020

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