From c6ef7456798cf6a82d102c44b1f9d4524beab83a Mon Sep 17 00:00:00 2001 From: John MacFarlane Date: Tue, 11 Nov 2014 20:45:30 -0800 Subject: Revised README. --- README.md | 98 +++++++++++++++++++++++++++++++++++++-------------------------- 1 file changed, 58 insertions(+), 40 deletions(-) (limited to 'README.md') diff --git a/README.md b/README.md index 54e2786..66c312d 100644 --- a/README.md +++ b/README.md @@ -10,17 +10,10 @@ The implementations The C implementation provides both a library and a standalone program `cmark` that converts CommonMark to HTML. It is written in standard C99 -and has no library dependencies. (However, if you check it out from the -repository, you'll need [`re2c`](http://re2c.org) to generate -`scanners.c` from `scanners.re`. This is only a build dependency for -developers, since `scanners.c` can be provided in a released source -tarball.) - -The parser is very fast, on par with +and has no library dependencies. The parser is very fast, on par with [sundown](https://github.com/vmg/sundown). Some benchmarks (on an ancient Thinkpad running Intel Core 2 Duo at 2GHz, measured using -`time` and parsing a -~500K book, the English version of [*Pro +`time` and parsing a ~500K book, the English version of [*Pro Git*](https://github.com/progit/progit/tree/master/en) by Scott Chacon and Ben Straub): @@ -35,61 +28,82 @@ Scott Chacon and Ben Straub): | **cmark** | 0.020s| 1.1| | sundown | 0.018s| 1.0| - Usage: cmark [FILE*] - Options: --help, -h Print usage information - --ast Print AST instead of HTML - --version Print version The JavaScript implementation is a single JavaScript file, with -no dependencies, that can be linked to in an HTML page. To build, -it, do `make js/commonmark.js` (this requires `browserify`, which you -can get using `npm install -g browserify`). You can also fetch -a pre-built copy from `http://spec.commonmark.org/js/commonmark.js`. -A command-line version (using `node.js`) is also provided -(`js/bin/commonmark`), and there is a "dingus" for playing with it -interactively. (`make dingus` will start this.) +no dependencies, that can be linked to in an HTML page. A node +package is also available; it includes a command-line tool called +`commonmark`. [Try it now!](http://jgm.github.io/CommonMark/js/) -**Note:** neither implementation attempts to sanitize link attributes or -raw HTML. If you use these libraries in applications that accept -untrusted user input, you must run the output through an HTML -sanitizer to protect against -[XSS attacks](http://en.wikipedia.org/wiki/Cross-site_scripting). - -[The spec] contains over 500 embedded examples which serve as conformance -tests. To run the tests for `cmark`, do `make test`. To run them for -another Markdown program, say `myprog`, do `make test PROG=myprog`. To -run the tests for `commonmark.js`, do `make testjs`. - -[The spec]: http://jgm.github.io/CommonMark/spec.html - Installing ---------- -To install the C program (and shared library), [cmake] is required: +Building the C program (`cmark`) and shared library (`libcmark`) +requires [cmake] and [`re2c`](http://re2c.org), which is used to +generate `scanners.c` from `scanners.re`. (Note that `re2c` is only a +build dependency for developers, since `scanners.c` can be provided in a +released source tarball.) + +On \*nix systems, you can simply `make` and `make install`. This +calls `cmake` to create a `Makefile` in the `build` directory, +then uses that `Makefile` to create the executable and library. + +Alternatively, you can use `cmake` manually. `cmake` knows how +to create build environments for many build systems. For +example, to create Xcode project files on OSX: mkdir build cd build - cmake .. # optionally: -DCMAKE_INSTALL_PREFIX=path - make # executable will be created as build/src/cmake + cmake -G Xcode .. # optionally: -DCMAKE_INSTALL_PREFIX=path + make # executable will be created as build/src/cmake make install To run tests: + make test + +or + perl runtests.pl spec.txt build/src/cmark -To build the javascript library: +The JavaScript library can be installed through `npm`: + + npm install commonmark + +To build the JavaScript library as a single standalone file: browserify --standalone commonmark js/lib/index.js -o js/commonmark.js -To run tests: +Or fetch a pre-built copy from +`. + +To run tests for the JavaScript library: node js/test.js +`make dingus` will start an interactive dingus you can use to +play with the JavaScript implementation: + +A note on security +------------------ + +Neither implementation attempts to sanitize link attributes or +raw HTML. If you use these libraries in applications that accept +untrusted user input, you must run the output through an HTML +sanitizer to protect against +[XSS attacks](http://en.wikipedia.org/wiki/Cross-site_scripting). + The spec -------- +[The spec] contains over 500 embedded examples which serve as conformance +tests. To run the tests for `cmark`, do `make test`. To run them for +another Markdown program, say `myprog`, do `make test PROG=myprog`. To +run the tests for `commonmark.js`, do `make testjs`. + +[The spec]: http://jgm.github.io/CommonMark/spec.html + The source of [the spec] is `spec.txt`. This is basically a Markdown file, with code examples written in a shorthand form: @@ -101,7 +115,7 @@ file, with code examples written in a shorthand form: To build an HTML version of the spec, do `make spec.html`. To build a PDF version, do `make spec.pdf`. Both these commands require that -pandoc is installed, and creating a PDF requires a latex installation. +[pandoc] is installed, and creating a PDF requires a latex installation. The spec is written from the point of view of the human writer, not the computer reader. It is not an algorithm---an English translation of @@ -131,6 +145,9 @@ like footnotes and definition lists. It is important to get the core right before considering such things. However, I have included a visible syntax for line breaks and fenced code blocks. +Differences from original Markdown +---------------------------------- + There are only a few places where this spec says things that contradict the canonical syntax description: @@ -210,7 +227,7 @@ based on PEG grammars and responding to years of user feedback have given me a good sense of the complexities involved in parsing Markdown, and of the various design decisions that can be made. I have also explored differences between -Markdown implementations extensively using [babelmark +Markdown implementations extensively using [BabelMark 2](http://johnmacfarlane.net/babelmark2/). In the early phases of working out the spec, I benefited greatly from collaboration with David Greenspan, and from feedback from several industrial users of Markdown, @@ -226,4 +243,5 @@ Use the [github issue tracker](http://github.com/jgm/stmd/issues) only for simple, clear, actionable issues. [cmake]: http://www.cmake.org/download/ +[pandoc]: http://johnmacfarlane.net/pandoc/ -- cgit v1.2.3