[fpc-pascal] named parameter

noreply at z505.com noreply at z505.com
Sat May 27 22:14:20 CEST 2017


On 2017-05-27 01:17, Mr Bee via fpc-pascal wrote:
> Hi,
> 
> As Pascal mostly well known as a safe, easy to read, and elegant
> language, don't you think Pascal needs named parameter? I mean for ALL
> kind of parameters, not just for Variants. When you have a function
> with many parameters having default values, you know that named
> parameter is desirable. For example:
> 
> function f(p1: string = ''; p2: integer = 0; p3: boolean = false);
> 
> But you only need to supply the third parameter, you still must supply
> the first and second ones with appropriate default values, like this:
> 
> f('', 0, true);
> 
> while with named parameter, you can do this:
> 
> f(p3 := true);
> ;

You can do something similar already with source comments

SomeProc(true {p3})

or

SomeProc({p3} true);

But obviously the compiler doesn't check it.

Problem is it increases the verbosity of the code, and how would the 
compiler determine when to check these and when not to... If you check 
this all the time it makes the language much more verbose and tedious 
for small functions like inttostr that you use all the time.

IMO though it does improve readability in long functions with lots of 
parameters, like windows api style procedures that have 5 or more 
parameters and you can't figure out which param is which



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