Loop iterator - example.txt

[kris]

Walter Bright wrote:
> Derek Parnell wrote:
> 
>> The use of 'goto' has an inherinent cost in terms of ongoing 
>> maintenance of code. In short, it adds to the time it takes to analyse 
>> code prior to making changes that do not have unintended side-effects. 
>> That cost must be justifed. Therefore one should only use 'goto' in 
>> situation in which the cost of its use can be offset by some other 
>> gain in the code. Such a gain is performance in a performace-critical 
>> section of code. I'm not sure if there are any other situations it is 
>> cost-justified.
> 
> 
> A goto is also useful:
> 
> 1) to avoid excessive diffs caused by refactoring code
> 
> 2) when one wants to build a control structure that just doesn't fit 
> into the usual if-else, while, for, etc.
> 
> 3) to avoid the creation of silly 'flag' state variables
> 
> 4) to create an efficient state machine
> 
> 5) as output from program generators
> 
> 6) to, for instance, collect all error handling code in one spot in a 
> function


#4 is definately useful within a switch(){}

Alternate design strategies aside, I was always told that goto, in 
general, lead to *less* efficient code. Didn't compilers (perhaps in the 
past) disable the optimizer for functions with one or more instances of 
goto? Doesn't it mess with flow analysis, or something?