From 7822379c703ceda824b6c916c4a7ed9df3425a37 Mon Sep 17 00:00:00 2001 From: David Majda Date: Sat, 17 Apr 2010 11:49:18 +0200 Subject: [PATCH] Rewrote the "Usage" section. --- README.md | 57 +++++++++++++++++++++++++++---------------------------- 1 file changed, 28 insertions(+), 29 deletions(-) diff --git a/README.md b/README.md index e71ebe7..db9527e 100644 --- a/README.md +++ b/README.md @@ -21,41 +21,40 @@ To use PEG.js, you need to generate a parser from your grammar and then use the ### Generating a Parser -A parser can be generated either [online](http://pegjs.majda.cz/online) in your browser or using the command line. Let's look at the second option. You need to follow these steps: - - 1. Install Java. This is necessary to run [Rhino](http://www.mozilla.org/rhino/) (which is bundled with PEG.js). - - 2. Generate the parser using `bin/pegjs` script on Unix or `bin/pegjs.bat` batch file on Windows. - -For example, to generate a parser from an example grammar in the `examples/arithmetics.pegjs` file on Unix, run: +To generate a parser, you can use the [online generator](http://pegjs.majda.cz/online) or the command line. For the second option, you need to have Java installed. Than you can generate the parser using the `bin/pegjs` script on Unix or `bin/pegjs.bat` batch file on Windows: $ bin/pegjs arithmeticsParser examples/arithmetics.pegjs -This command will create the parser in the `examples/arithmetics.js` file and will make it available in the `arithmeticsParser` global variable. - -The `bin/pegjs` command has several options that influence the generator—to learn more about them, use the `--help` option. - -**Note:** In the future, I will probably use [Narwhal](http://narwhaljs.org/) for the command-line version. +This command will create the parser from the `examples/arithmetics.pegjs` file and put in into the `examples/arithmetics.js` file. The generated parser will be available in the `arithmeticsParser` global variable. The generator has several useful options—to learn more about them, use `--help`. ### Using the Generated Parser -Let's assume that you want to use the parser in a web page. To do this, you need to: - - 1. Include the generated parser into your page: - - - - - This creates a variable with the parser object in the global scope (you can choose name of the variable when generating the parser). - - 2. Use the parser, i.e. call the `parse` method on the parser variable: - - - - The `parse` method of the generated parser will return either the result of the parsing (dependent on the actions you specified in the grammar) or throw `PEG.Parser.SyntaxError` exception if the input contains a syntax error. The exception has properties `message`, `line` and `column`, which contain details about the error. +To use the parser in a web page, follow the following example: + + + + Arithmetics Parser Example + + + + + + +
+ + +The `parse` method of the generated parser will return either the result of the parsing (dependent on the actions you specified in the grammar) or throw `PEG.Parser.SyntaxError` exception if the input contains a syntax error. The exception has properties `message`, `line` and `column`, which contain details about the error. Grammar -------