Type operators

njet.org

Anvil

Documentation

Language reference

Expressions

Type operators

Type operators are used to check if some expression evaluates to a given type.

Is	Type of expression...
`defined`	Is defined, i.e., not `anvil.lang.undefined`.
`undefined`	Is `anvil.lang.undefined`.
`null`	Is `anvil.lang.null`.
`boolean`	Is `anvil.lang.boolean`.
`int`	Is `anvil.lang.int`.
`float`	Is `anvil.lang.float`.
`string`	Is `anvil.lang.string`.
`..`	Is `anvil.lang.range`.
`()`	Is `anvil.lang.tuple`.
`{}`	Is `anvil.lang.list`.
`[]`	Is `anvil.lang.array`.
`class`	Is a class.
`&`	Is a ref.
identifier	Is of a given type; identifier must point to a class or interface.

If ``isДД if followed by ``!ДД the meaning of expression is negated. Read as, "x is NOT y".

  is-expr := expr "is" ["!"] "defined" 
  is-expr := expr "is" ["!"] "undefined" 
  is-expr := expr "is" ["!"] "null" 
  is-expr := expr "is" ["!"] "boolean" 
  is-expr := expr "is" ["!"] "int" 
  is-expr := expr "is" ["!"] "float" 
  is-expr := expr "is" ["!"] "string" 
  is-expr := expr "is" ["!"] "&" 
  is-expr := expr "is" ["!"] ".." 
  is-expr := expr "is" ["!"] "=>" 
  is-expr := expr "is" ["!"] "(" ")" 
  is-expr := expr "is" ["!"] "{" "}" 
  is-expr := expr "is" ["!"] "[" "]" 
  is-expr := expr "is" ["!"] "class" 
  is-expr := expr "is" ["!"] entity_{class-of-interface}

See also | Expressions | Grammar

Contributes notes:

Add a note

Anvil