/snm-parser

Primary LanguagePython

SNM Grammar Specification

Install Lark

$ pip3 install lark-parser  # pip if in Windows environment

Operator Precedence (High to Low)

  • +, - Unary plus and minus
    • -1
    • --+100 -> 100
    • ++++100 -> 100
    • ---100 -> -100
  • in -> list operation
    • "abc" in ["abc", "def"] -> true
    • 1 in [1, 2, 3,] -> true
    • [1, 2] in [1, 2, 4, 6] -> true
    • [0, 2] in [1, 2, 3] -> false
    • !1 in [true, false] -> false
      • 1 in [true, false] is evaluated first!
  • ! Logical not
    • !false -> true
    • !100 -> false
    • !0 -> true
  • *, /, % Multiplication, division, and remainder
  • +, - Addition and subtraction
  • <, <=, >, >= Relational operators <, ≤, >, ≥
  • ==, != Relational = and ≠ respectively
  • && Logical AND
  • || Logical OR

Data Types

  • String: "string"
  • Number: 123, -123
  • Boolean: true, false
  • Array: [1, 3, "hello", [123, 456], true, false]
    • An array can contain any data types
  • Field:
    • e.g. age, AGE, age_01, i_am_a_field
    • Field name should contain only numbers, letters and underline _
    • No special characters are allowed 👈