setFnWriteProtect

setFnWriteProtect( 
s_name 
) 
=> t / nil

Description

Prevents a named function from being redefined.

If s_name has a function value, it can no longer be changed. If it does not have a function value but does have an autoload property, the autoload is still allowed. This is treated as a special case so that all the desired functions can be write-protected first and autoloaded as needed.

Arguments

s_name

Name of the function.

Value Returned

t	The function is now write protected.
nil	If the function is already write protected.

Examples

Define a function and set its write protection so it cannot be redefined.

procedure( test() println( "Called function test" ))
setFnWriteProtect( 'test ) => t

procedure( test() println( "Redefine function test" ))

*Error* def: function name already in use and cannot be 
    redefined - test

setFnWriteProtect( 'plus ) => nil

Returns nil because the plus function is already write protected.

Related Topics

Function and Program Structure

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