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A checklist for creating a new Tree Language from Scratch

  • Know where to get help. GitHub issues, Tree Notation subreddit, Google Groups, or email Breck.
  • Take a look at some of the sample languages in the simple web Tree Language builder. You might be able to use these as a reference if you get stuck.
  • Open the Tree Language builder or use your own editor (note: only Sublime Text 3 currently has syntax highlighting for Grammar Languages).
  • Name your language. For now, it is recommended that your language name be lowercase, only letters between A-Z, and not a common reserved word like "while/if/true/etc". You are free to name it anything you want, but if you do we ask that you report any bugs you encounter.
  • If you are using the Tree Language builder, clear the boxes to create a new language from scratch. If you are using your own editor, create a new file with the name "{yourLanguageNameGoesHere}.grammar"
  • Create a root nodeType. This will be the root node for your language. It should like this:
{yourLanguageNameGoesHere}Node
 root
  • Add a description line to your new root nodeType. This should describe what the purpose of your language is:
{yourLanguageNameGoesHere}Node
 root
 description {thisIsALangageToHelpYouDoX}
  • Add a top level nodeType to your language. In this example, we'll make a simple language that allows to store your friend's birthdays. Let's add a "friend" nodeType.
birthdaysNode
 root
 description A language for storing your friend's birthdays.
friendNode
 description Store information about a friend.
  • Now let's add an inScope line to the root node so that the friend node is in scope:
birthdaysNode
 root
 description A language for storing your friend's birthdays.
 inScope friendNode
friendNode
 description Store information about a friend.
  • Now the following is a valid program in your language:
friend
friend
friend
  • Now let's add a "name" nodeType under the friend nodeType's scope. We're start hiding some already mentioned code with "..."
...
friendNode
 description Store information about a friend.
 inScope nameNode
nameNode
  • Now the following is a valid program in your language:
friend
 name
friend
 name
...
  • Now let's add a "cellType", which let's us start getting things like type checking, syntax highlighting, and autocomplete. By the current convention, we put the cellTypes at the top of our grammar file.
nameCell
 highlightScope string
...
  • Now let's make the name nodeType accept a "catch all" cellType of the nameCell.
...
nameNode
 catchAllCellType nameCell
  • Now the following is a valid program in your language:
friend
 name Ben Franklin
friend
 name Ada Lovelace
  • Now let's add an error nodeType, and link it to the rootNode, to catch errors:
birthdaysNode
 root
 description A language for storing your friend's birthdays.
 inScope friendNode
 catchAllNodeType errorNode
errorNode
 baseNodeType errorNode
  • Now you should get an error for a program like this:
frieeeend
 name Ben Franklin

That's all for now! Let us know what you need to do next.

Of course, we haven't really gotten to the fun stuff yet. Languages get really interesting once you start implementing the "interesting methods", like compile, execute, render, and format.