Explain Tokens, Keywords, and comments in the F# Language | F# Tutorial

Explaining Tokens, Keywords, and comments in the F# Programming Language

In this article, you will understand the basic terminology of the F# language.

Tokens in F# Programming:

F# programming language has multiple tokens. A token can be a keyword, an identifier, a string literal, a constant, or a symbol. The token in F# is of two types:

• Keywords
• Strings and Literals.

Keywords in F# Programming

Keywords are words whose meaning is pre-defined in the programming language. It can not be used as variables and literals. The keywords used in the F# are:

Keywords with their description

- abstract

   It indicates that either the method is not implemented in the type it is declared or it is virtual and not implemented anywhere.

- and

   It is especially used in mutually recursive bindings, declaration in property, and with various constraints in generic parameters.

- as

   It is used in giving the name of the present class object to an object name. It is also used in giving the name to an entire pattern inside the pattern match.

- assert

   It is used to verify the code after performing debugging.

- base

   It is used as a name for the present class object.

- begin

   It indicates the start of the code.

- class

   The definition of the class starts from this word.

- default

  It defines the indication of an abstract method. It can be used with an abstract method declaration to create a virtual method.

- delegate

   It is used in the declaration of the delegate.

- do

   It is used in looping constructs or to execute vital code.

- done

   It points to the end of the code in a looping expression.

- downcast

  It is used to convert to a type that is lower in the inheritance chain.

- elif

   It is used in conditional formatting.

- else

   It is used in conditional branching.

- exception

   It is used in exception declaration.

- false

   It is used in a boolean literal.

- finally

   It executes the block of code regardless of whether the output of the exception is true or false.

- for 

   It is looping branching.

- function

   It is used in the shorter alternative to the fun keyword.

- if

  It is used in conditional formatting.

- interface

   It is used in declaring and implementing interfaces.

- member

   It is used as a property and method in an object type.

- private

   It restricts the access to a member to code in the same type.

- public

  It allows access to a member from outside the type.

Comments in F# programming language

It has two types of comments:

• One Line comment: It is represented by using the// symbol.
• Multi-Line comment: It starts with * and ends with *.