On Sun, Nov 24, 2013 at 1:53 PM, Martin Schreiber <[email protected]> wrote: > On Sunday 24 November 2013 14:48:05 Marcos Douglas wrote: >> You can not protect the programmers using this. Think. Even if you use >> 'return', 'result', whatever... if the programmer put a Exit on your >> code the same error will happen! Bad programmers do it. They forget to >> create some object, don't destroy them, etc. Who cares! No language >> can protect all source. > > OK, I'll remove 'return' from MSElang, one source less (MSElang has > no 'exit'). ;-) > The argument is, it should be possible to program without 'return' if one > wants a safe coding style therefore the assignment at function end.
I disagree that a program without 'return' or 'exit' uses a more safe coding style. IMO the 'exit' is indispensable for write a more simpler code. " function test(a: int32, b: int32, c: int32): int32; begin result:= 0; //initilization if (a=0) and (b=0) and (c=0) then exit; // doesn't matter anymore, args are wrong! if a=-1 then result:= 123; else begin if (b=0) or (c=0) then begin result:= -100; else result:= 88; end; " >> Pardon me but your algorithm -- I know this is just an example -- is >> wrong. You do not need to use GOTO. >> Using the real Pascal: >> " >> begin >> result:= 0; //initilization >> if a then //long deeply nested processing >> result:= 123 >> else >> begin >> if b and c then >> result:= -100 >> else >> begin >> if not (a or b) then >> begin >> result := 1000; >> globflag:= true; >> exit; >> end >> else >> result:= 88; >> end; >> end; >> globflag:= result > 0; >> end; >> " > The two things every Delphi expert writes: > - *never* use 'goto', it is dirty! > - do *not* use 'with', it is evil! I use 'goto' (rare cases) and use 'with' a lot (but we know problems exist). > Because I am no Delphi expert I think both statements are wrong. ;-) > The 'exit' (or return) statement actually is a "goto end". I just guess the 'exit' is wrong because should be a keyword not a function -- like 'return' -- but it must exists. > A 'goto' has a 'label' definition in header and a left aligned label, much > better than 'exit' which easy can be overlooked. Maybe 'goto' can be more explicit than 'exit' but more problems could exists using 'goto' instead 'exit'. Using 'exit' there is no error unless the programmer has not initialized the return. Using 'goto' you will can write a algorithm that never will exit from de function, poor algorithm, etc. -- Marcos Douglas ------------------------------------------------------------------------------ Shape the Mobile Experience: Free Subscription Software experts and developers: Be at the forefront of tech innovation. Intel(R) Software Adrenaline delivers strategic insight and game-changing conversations that shape the rapidly evolving mobile landscape. Sign up now. http://pubads.g.doubleclick.net/gampad/clk?id=63431311&iu=/4140/ostg.clktrk _______________________________________________ mseide-msegui-talk mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/mseide-msegui-talk
