LPE parser

Two grammars

Standard LPE grammar

basically follows LISP notation but written with C-like function call semantics. Example:

Dot (

) separated function calls will compose to left thread

->

call:

["->",["f1",1,"b","c"],["f2","d","e","f"],["f3","w"]]

Semicolon (

;

) separated function calls will compose to

begin

call:

["begin",["f1",1,"b","c"],["f2","d","e","f"],["f3","w"]]

Arrays notation

will result in

[

call:

[1,2,3]

=>

["[","1","2","3"]

Logical LPE grammar

Some functions will have special syntax for their arguments. Currently only

syntax is supported. For example, it is used for

where

function, which has single logical expression argument with 3 operations:

and

,

or

,

not

. Logical operations may use any LPE expression as argumants. Brackets are preserved with call to obvious

()

function.

[
  "where",
  [
    "or",
    [
      "()",
      [
        "and",
        "a",
        [
          "or",
          "b",
          "c"
        ]
      ]
    ],
    [
      "or",
      [
        "()",
        [
          "<",
          [
            "avg",
            "d"
          ],
          [
            "avg",
            "e"
          ]
        ]
      ],
      [
        "()",
        [
          "and",
          [
            "=",
            "e",
            20
          ],
          [
            "parse_kv",
            [
              "->",
              "locations",
              "src_id"
            ]
          ]
        ]
      ]
    ]
  ]
]

Note, that dot notation in arguments

is currently interpreted as

->

call.

Run from cli

Tests

Run tests:

npm run test

npm run test-sql