err

err( 
[ g_value ] 
) 
=> none

Description

Causes an error.

If this error is caught by an errset, nil is returned by that errset. However, if the optional g_value argument is given then g_value is returned from the errset and can be used to identify which err signaled the error. The err function never returns a value.

Arguments

g_value

SKILL object that becomes the return value for errset.

Value Returned

Never returns a value.

Examples

errset( err( 'ErrorType))        
=> (ErrorType)
errset.errset                    
=> nil

procedure( test( x )
    if( (equal errset( foo( x )) '(throw))
        then println( "Throw caught" )
        else if( errset.errset println( "Error: divide by
                    zero"))))=> test
procedure( foo( x )
    if( (equal (4 / x) 1) 
        then err( 'throw ) 
        else println( x )))=> foo

test( 4 ) => nil         ; Prints Throw caught
test( 2 ) => nil         ; Prints 2
test( 0 ) => nil         ; Prints Error: divide by zero

Related Topics

Function and Program Structure

error

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