TYPEOF

• Source: https://www.freebasic.net/wiki/wikka.php?wakka=KeyPgTypeof
• Last revised: 2024-02-25

---

Returns the type of a variable.

Syntax

` Typeof ( variable | datatype )

`

Parameters

variable

A variable of any type.

datatype

A DataType.

Description

Typeof is a compiler intrinsic that replaces itself with the type of the variable passed to it. It can either be used in a variable declaration (Example 1) or it can be used in the preprocessor for comparison, printing. (Example 2)

Typeof also supports passing any intrinsic data type, or user-defined type (and its data fields), not only variables defined as those types. Also supported are expressions, the type is inferred from the expression (much like Var).

If there is both a user defined type and a variable visible with the same name in the current scope, the user defined type takes precedence over the variable. To ensure that the Typeof takes the variable instead of the user defined type, wrap the argument to Typeof with parentheses to force it to be seen as an expression. For example Typeof((variable)).

Examples

Example 1:

start GeSHi

Dim As Integer foo
Dim As TypeOf(67.2) bar '' '67.2' is a literal double
Dim As TypeOf( foo + bar ) teh_double '' double + integer results in double
Print SizeOf(teh_double)

end GeSHi

Example 2:

start GeSHi

Dim As String foo
#print TypeOf(foo)
#if TypeOf(foo) = TypeOf(Integer)
  #print "Never happened!"
#endif

#if TypeOf(foo) = TypeOf(String)
  #print "It's a String!"
#endif

end GeSHi

Version

• Before fbc 1.10.0, Typeof was not returning the type of the non-static member procedures of a UDT.
• Before fbc 1.08.0:

Dialect Differences

• Not available in the -lang qb dialect unless referenced with the alias __Typeof.

Differences from QB

• New to FreeBASIC

See also

• Sizeof
• Var
• Type (Alias)
• Type...End Type

Back to DocToc