Please note that this site is an alpha-stage prototype under rapid development. It is likely to change often and, at times, some features may be broken or only partially implemented.
Click next for an extremely brief tour.
You can watch see this again at any time by clicking "Help" at the top of the screen.
To start, you enter your PEG.js grammar here.
The text that your PEG.js grammar will be parsing goes here.
Here's where you click to build your parser.
Select one of the three tabs below to inspect your parser's results.
This is where you can see the JSON representation of the parse tree produced by your PEG.
Thanks to the library, d3.js, you don't need an imagination to visualize your parse tree!
This tab shows the results of traversing your parse tree...
Essentially, it's what you'd see if your program ran in a console.
Click here to pick one of the sample grammars.