intent

How a procedure uses a dummy argument, and what role a variable plays.

Declaration

Syntax

intent = Local | In | Out | InOut | ReturnVar | Unspecified

Values

Value	Meaning
Local	a local variable, not an argument.
In	intent(in): the argument is read and must not be written.
Out	intent(out): the argument is written before it is read. Its value on entry is undefined.
InOut	intent(inout): the argument is both read and written.
ReturnVar	the result variable of a function.
Unspecified	a dummy argument with no intent attribute. Whether the procedure writes through it is not known here.

Return values

None. An enumeration value is not evaluated.

Description

The intent is a contract the call site has to satisfy: an actual argument for an Out or InOut dummy must be writable, which means a variable expression or a cast wrapper around one. For In and Unspecified any expression is allowed.

Local and ReturnVar are not argument intents at all: they identify what the variable is. Every Variable carries one of these six values, so the role of a symbol is never inferred from where it appears.

See Also

Variable, Function, SubroutineCall, FunctionCall