Chapter 11 The OCaml language

5 Constants

constant::= integer-literal
  int32-literal
  int64-literal
  nativeint-literal
  float-literal
  char-literal
  string-literal
  constr
  false
  true
  ()
  begin end
  []
  [||]
  `tag-name

See also the following language extension: extension literals.

The syntactic class of constants comprises literals from the four base types (integers, floating-point numbers, characters, character strings), the integer variants, and constant constructors from both normal and polymorphic variants, as well as the special constants false, true, (), [], and [||], which behave like constant constructors, and begin end, which is equivalent to ().