hello monks:

I am try to create a simple subroutine. Basically copied the example from Learning Perl pg 59. The error message is:
Can't modify constant item in list assignment at loadBofATradesB.pl line 156, near "@_;" This is my subroutine
sub fieldString {
  my($strIn, $typeIn);    #this is line 156
  ($strIn,  typeIn)  =  @_;
    $strIn = trim(strIn);
    
  
  $rtnVal = undef;
  
  if ( length($strIn) ==  0 ) {
    $rtnVal = 'NULL'; 
  
  }
  else  {
    if (typeIn == 'N')  {
       $retVal = $strIn;   
     }  
     else  {
        $retVal = "'$strIn'";   
     
     }  
  
  }
  
  $retVal;

}


 
# Perl trim function to remove whitespace from the start and end of th
+e string
sub trim($)
{
    my $string = shift;
    $string =~ s/^\s+//;
    $string =~ s/\s+$//;
    return $string;
}

[download]

I do not understand my mistake.

kd

In reply to will not compile by kevind0718

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