Re: [fpc-pascal] a few trivial questions

[Michael Van Canneyt]

On Wed, 12 May 2010, spir ☣ wrote:

Hello,

* TFPList
Is there another way to traverse a list than
   for i :=0 to (list.count - 1) do ...

You can use an enumerator with the latest SVN:

foreach P in List do

What about list.high?

Count=High.

Also, is it possible to set a list's base index to 1 (so that last_index=count)?

No. That would break all other existing code.

There is a super handy forEachCall method (calling a proc for each item), but I 
cannot find a matching map method (calling a func and storing results).

What do you mean with 'Map' ?

* string <-> number
I could not find _functions_ to operate such conversions, only _procedures_ str 
and val. So that I always end up with superfluous statements and temps 
variables:
   str(n,text);
   writeln(text);

In SysUtils: StrToInt() and IntToStr()

vs
   writeln(NumbetToString(n));
Ok, I can write these funcs (I did ;-). But how comes there are no builtin 
functions for that?

They exist; you simply don't know them.

* string section

Is there another way to slice a string than using copy. In particuliar, the count argument is not always practical to indicate the end_of_section position. (count = last-first+1)

I think that LeftStr and RightStr exist in strutils.

* array value notation
I can set a static array's value on declaration line, but could not find a way 
to do it later (even less to change it). And I cannot find a way to set the 
value of a dynamic array --when it's not fed from a loop. End up with series of 
arr[i]:=v statements (code from the http://en.wikipedia.org/wiki/Middle_ages 
;-). Same for lists, indeed.
   var
       arr : array [1..2] of Integer;
   ...
   i:=1 ; j:=2;
   arr := (i,j);
   ==> Syntax error, ")" expected, but "," found

This is only possible with dynamic arrays (no declared length), and there you 
should use setlength.

Finally: is there a wiki version of the official docs, to collectively enhance them (with notes, examples, explanations...). (I'm dreaming, but after all fpc is free software, and it's the #1 reason why I chose it.) (*)

No, there is no wiki version, and there never will be.

Michael.
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