lambda-expressions syntax

Lambda-expression syntax

• Variable
  any identifier beginning with a lower case letter
  (ex. x, y, z, add, fac, etc.).
• Constant
  an integer, an operator or any identifier beginning with an upper case letter.
  (some constant are predefined)
  (ex. +, *, TRUE, FALSE, etc.)
• Abstraction: Symbol "\" is used instead of the letter Lambda of the Greek alphabet.
  \ x . E
  (ex. \x.x, \x.\y.x, etc.)
• Application: Notation for application is juxtaposition.
  E1 E2
  (ex. fax 3, x y z, etc.)

Syntax uses usual parenthesing conventions: application priority is greater than abstraction one and application is left associative.