@gram-data/gram-format

gram-ast

Graph model abstract syntax tree.

////////
// unit: an empty path expression
[]
[] . [] = []

// identity
identityof [] = undefined || all the same?
identityof [n] =~ n


////////
// node: an identified path expression with no children
(n) =~ [n]
identityof (n) =~ n
identityof ()  =~ <auto>

// composition of nodes and units
(n) . []   =~ [ . n _ ]  =~ [n] =~ (n)
[]  . (n)  =~ [ . _ n ]  =~ [n] =~ (n)
(n) . (n)  =~ [ . n n ]
(n) . (n2) =~ [ . n n2]
identityof [ . n n ]  =~ <auto>
identityof [e . n n2] =~ e

////////
// edge: an identified path expression composed of two nodes
[n] . [n] =~ [e . [n] [n]]
[e . (n1) (n2)]
[e1] . [e2] =~ [p] 

////////
// path: an identified path expression composed of path expressions 

// unary path operations
[p [u]] =~ [p]
[p [e]]
[p (n)]
[p [p2]]
[p [p]] =~ [p]

// binary path operations with unit produce the non-unit operand
(n) =~ (n) . []
(n) =~ []  . (n)
[e] =~ [e] . []
[e] =~ []  . [e]
[p] =~ [p] . []
[p] =~ []  . [p]

// binary path operations with non-unit
[p [e]  . [p2]]  =~ [e]  . [p2]
[p [e]  . [e] ]  =~ [e]  . [e]
[p [e]  . (n) ]  =~ [e]  . (n)
[p (n)  . [p2]]  =~ (n)  . [p2]
[p (n)  . [e] ]  =~ (n)  . [e]
[p (n)  . (n) ]  =~ (n)  . (n)   // aka an edge!
[p [p1] . [p2]]  =~ [p1] . [p2]
[p [p1] . [e]]   =~ [p1] . [e]
[p [p1] . (n)    =~ [p1] . (n)

Library Components

• gram-tokens with regular expressions to tokenize text
• gram-ast Abstract Syntax Tree type specifications
• gram-builder to compose a gram AST
• gram-find to traverse a gram AST
• gram-transform to process a gram AST
• gram-stringify to pretty print the AST
• gram-parse derived from gram.ne to parse text into an AST

Demo

Developer instructions

This project was bootstrapped with TSDX.

• yarn build to build the parser and assemble a distribution
• yarn link to get a locally linked gram-lint binary

Credits

Thanks to these project for inspiration:

• The entire unist family
• mdast-builder for how to make a builder