is_binary : string -> term -> bool

SYNOPSIS

Tests if a term is an application of a named binary operator.

DESCRIPTION

The call is_binary s tm tests if term tm is an instance of a binary operator (op l) r where op is a constant with name s. If so, it returns true; otherwise it returns false. Note that op is required to be a constant.

FAILURE CONDITIONS

Never fails.

EXAMPLE

This one succeeds:

  # is_binary "+" `1 + 2`;;
  val it : bool = true

but this one fails unless f has been declared a constant:

  # is_binary "f" `f x y`;;
  Warning: inventing type variables
  val it : bool = false