> I've been trying to understand this segment of code:-
>
> vals := ldap getValues: entry attribute: attr.
> vals isNull ifFalse: [
> val := vals.
> [ val value isNil ] whileFalse: [
> (attr->val value) printNl.
> val incr ].
> ]
>
> When I look at the orginal C source, vals is just an array of strings
> and it just requires a simple _for_ loop to print out all the values.
> One wonders why the Smalltalk code is so verbose.
Because Smalltalk has no for(A=B;*A;A++) statement:
val := vals "A=B"
[val value isNil ] "*A != NULL" whileFalse: [
...
val incr "A++"
]
> val := vals.
> " why the need to copy val to another variable? Is this just in case
> we decide to update vals?"
To free vals later.
> [ val value isNil ] whileFalse: [
> "So what does 'val value' represent? A pointer to an array?"
"val" is A, "val value" is "*A" i.e. the string.
> (attr->val value) printNl.
> "'attr->val value'. This is the one I really don't understand. Why
> doesn't the array of strings come into Smalltalk as just that; an array
> of strings, then all one has to to is step through the array? Instead
> we're getting the value from an association..?"
No, that's wrong! I'm just replacing
printf ("%s %s\n", attr, *val);
with printing an association. It's less verbose than
('%1 %2' % { attr. val value }) printNl.
but maybe the latter is clearer.
Paolo
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