Difference between revisions of "Talk:Modernised Pascal"

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(whats the point of elseif)
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- Non-reusable variables. Most of the time you don't need and you don't want to assign unrelated values to a variable repeatedly (i.e. you only need to use ':=' once on it), just Inc, Dec, use in for loop, etc. To be allowed to reassign a variable it should have to be declared with a special directive.
 
- Non-reusable variables. Most of the time you don't need and you don't want to assign unrelated values to a variable repeatedly (i.e. you only need to use ':=' once on it), just Inc, Dec, use in for loop, etc. To be allowed to reassign a variable it should have to be declared with a special directive.
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== whats the point of elseif ==
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in a block based language like pascal? [[User:Plugwash|Plugwash]] 21:59, 4 June 2006 (CEST)

Revision as of 20:59, 4 June 2006

4) - that might make sense, if also applied to for, with, if, making 'begin' implicit everywhere, like it is done in Component Pascal. However it is major leap, and can be considered only in terms of implementin one more specific non-Borland mode. But personall i'd prefer implicit 'try' there :)

6) - as far as i got it, it is runtime variable initialisation, instead of compile-time one. Syntactic sugar of doubtful quality. I would say that may make sense together with 5), modifiyng with to make shortcuts to some subclasses, record members, whatever.

 with Addr = DataSet1.FieldByName['Address'], Phone=DataSet1.Field['Telephone'].AsInteger do 
      begin
           Addr.Value := Addr.Value + #13#10 + IntToStr(Phone)
      end;

Hence, turning with into bi-modal operator, like FROM clause in SQL SELECT, ehich can settle default table without alias and other tables with aliases.

However this a major change in compiler, and cons and pros are not clear. - '=' looks absoletely not Pascal-style here, replaccing it with 'is' is even worse, brand new keyword like "beeing" ? Pascal is to be small language, even is not as small as Component Pascal :) - Compiler would have hard time to decide what to stor in aliases: cached value read-only, pointer to original variable, pointer to some object returned by some function, make inline substitution or whatever. + Programmer is no more needed to settle teporary variables, and would never change or Dispose it by mistake. + Programmer have easy way to avoid multiple expensive functions calls, like .FieldByName is. However it would be not making new initialized variables, but rather an aliases to exisiting ones.

......... i tried to giggle here, but later decided to go main page :)

braindump

- It should be disallowed to call the constructor from an instace! Or it should have no result when calling from instance.

- "Abstract class" declaration like Java.

- "final" AKA "readonly" variables, a la Java and .Net.

- "final" methods and classes which cannot be overriden or extended, respectively, like in Java.

- "Removal of begin"? Nice :) The only interesting thing in VB (of course done badly :-/ ) is having a different block terminator for each block "type". I guess it would be nice to have these and implicit blocks in all conditionals and loops.

- Non-reusable variables. Most of the time you don't need and you don't want to assign unrelated values to a variable repeatedly (i.e. you only need to use ':=' once on it), just Inc, Dec, use in for loop, etc. To be allowed to reassign a variable it should have to be declared with a special directive.

whats the point of elseif

in a block based language like pascal? Plugwash 21:59, 4 June 2006 (CEST)