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### Author Topic: Set of strings (ordinal expression expected  (Read 2432 times)

#### bdexterholland

• New member
• Posts: 44
• uh?
##### Re: Set of strings (ordinal expression expected
« Reply #15 on: February 09, 2017, 04:33:49 pm »
Code: Pascal  [Select]
1. {\$ifdef fpc}{\$mode objfpc}{\$H+}{\$endif}
2. uses
3.   classes,sysutils;
4. const
5.   mystrings:array [0..26] of string = ('AC','AL','AP','AM','BA','CE',
6.     'DF','ES','GO','MA','MT','MS','MG','PA','PB','PR','PE','PI','RJ',
7.     'RN','RS','RO','RR','SC','SP','SE','TO');
8.
9.  operator in (const AVAlue:string;const A:array of string)c:Boolean;
10.  var L:TStringList;
11.  begin
12.    L := TStringList.Create;
13.    C := False;
14.    try
16.      C := L.IndexOf(AValue) <> -1;
17.    finally
18.      L.Free;
19.    end;
20.  end;
21.
22. var
23.  AValue:string;
24. begin
25.   AVAlue := 'SP';
26.   if AValue in mystrings then
27.     writeln('Found')
28.   else
30. end.
Can be more efficient, but you get the idea.

Lotta code for a simple problem.

[sleep .....]

• Hero Member
• Posts: 4248
##### Re: Set of strings (ordinal expression expected
« Reply #16 on: February 09, 2017, 04:38:05 pm »
It is a generic solution that you can re-use. So write once applies Not a lot of code for that... at all...

Thing is: set operators on strings do not exist, but you can overload all set operators to create that feature yourself
Put them in a unit, and hey presto! we have the behavior that you expected.
« Last Edit: February 09, 2017, 04:44:45 pm by Thaddy »
"Logically, no number of positive outcomes at the level of experimental testing can confirm a scientific theory, but a single counterexample is logically decisive."

#### bdexterholland

• New member
• Posts: 44
• uh?
##### Re: Set of strings (ordinal expression expected
« Reply #17 on: February 18, 2017, 02:27:43 pm »
well yeah, that's a good hint!

so, why i doesn't came onboard in fpc lib?
[sleep .....]

• Hero Member
• Posts: 4248
##### Re: Set of strings (ordinal expression expected
« Reply #18 on: February 18, 2017, 02:38:57 pm »
Because I didn't submit it?
It's trivial. And boring to code all of them. Once I need all of it, trust me, I will submit it

There's also the small matter of interpretation... But, oh, well...

For example: do you want it to work like a set or like a tuple?
« Last Edit: February 18, 2017, 03:01:03 pm by Thaddy »
"Logically, no number of positive outcomes at the level of experimental testing can confirm a scientific theory, but a single counterexample is logically decisive."