IDL_VALIDNAME

The IDL_VALIDNAME function determines whether a string may be used as a valid IDL variable name or structure tag name. Optionally, the routine can convert non-valid characters into underscores, returning a valid name string.

Syntax

Return Value

Returns the input string or strings, optionally converting all spaces or non-alphanumeric characters to underscores. If an input string cannot be used as a valid variable or structure tag name, a null string is returned.

Arguments

String

A scalar string or string array or representing the IDL variable or structure tag names to be checked.

Keywords

CONVERT_ALL

If this keyword is set, then each element of String is converted into a valid IDL variable name using the following rules:

All non-alphanumeric characters (except `_', `!' and `$') are converted to underscores

If the first character is a number or a `$', then an underscore is prepended to the string

If the first character is not a valid character (`_', `!', `A'...'Z') then that character is converted to an underscore

If the element of String is an empty string or a reserved word (such as "AND") then an underscore is prepended to the string

Tip
The CONVERT_ALL keyword guarantees that a valid variable name is returned. It is useful in converting user-supplied strings into valid IDL variable names.

CONVERT_SPACES

If this keyword is set, then all spaces within each element of String are converted to underscores. If an element of String contains any other non-alphanumeric characters, then a null string is returned, indicating that the string cannot be used as a valid variable name.

Examples

Table 3-49: IDL_VALIDNAME Examples

Table 3-49: IDL_VALIDNAME Examples
Example	Result
IDL_VALIDNAME('abc')	'abc'
IDL_VALIDNAME(' a b c ')	''
IDL_VALIDNAME(' a b c ', /CONVERT_SPACES)	'_a_b_c_'
IDL_VALIDNAME('$var')	''
IDL_VALIDNAME('$var', /CONVERT_ALL)	'_$VAR'
IDL_VALIDNAME('and')	''
IDL_VALIDNAME('and', /CONVERT_ALL)	'_AND'
IDL_VALIDNAME(['and', 'or'], /CONVERT_ALL)	['_AND', '_OR']

6.0	Introduced
6.4	Modified to accept string arrays as well as scalar strings