"Continue" function in loops.

[Bribe]

Ever wonder what to do in JASS in place of a "continue" function in a loop? This used to bother me a few years ago but the solution is simple when you think of it.

Problem:

loop
    //do stuff
    if condition then
        //continue
    endif
    //do stuff
    exitwhen loopIsDone
endloop

Solution:

loop
    loop
        //do stuff
        if condition then
            exitwhen true //continue
        endif
        //do stuff
        if loopIsDone then
            set exit=true
            exitwhen true
        endif
    endloop
    exitwhen exit
endloop

Hope this inspires!

 

[Adiktuz]

it could be just

exitwhen condition

right?

 

[GhostWolf]

Or structure your code properly so you don't need continue.

 

[Bribe]

Or structure your code properly so you don't need continue.

My example didn't show a case where it was actually needed, but I have run into structures where the complexity of what Is working with required a continue or nothing else. It is not always possible given an if/then statement.

@Adiktuz

A continue statement takes you to the top of a loop. My example had several ways out, but like I said the resources I've worked with sometimes have gotten into really complex if/then blocks and I'd wished for a continue statement. This example is very simple on purpose, but it's only for people who need it.

 

[Malhorne]

Normally you should not use break/continue ect...

 

[Bribe]

Normally you should not use break/continue ect...

Break and Continue are excellent functions to have.

 

[Cokemonkey11]

break and continue are useful in their own right, but this pseudo-continue structure you've made is entirely worse than just structuring the loop differently.

Consider:

loop
    // do stuff
    if not condition then
        // do stuff
    endif
    exitwhen loopIsDone
endloop

 

[Bribe]

You guys really meet this with a lot of negativity. If you don't need it, disregard the post. You are all completely ignoring what I've said about the example being simple but the need being more complex than what I've shown. I'll see if I can look through my resources and show you what I mean.

 

[edo494]

I actually like it, I use break; and continue; in C++ from time to time, and I implemented break; in Jass, but never thought of implementing continue;

 

[Cokemonkey11]

You guys really meet this with a lot of negativity. If you don't need it, disregard the post. You are all completely ignoring what I've said about the example being simple but the need being more complex than what I've shown. I'll see if I can look through my resources and show you what I mean.

It's nothing personal, I just can't think of a case where the nested loop

• looks better
• performs the same function more efficiently
• is easier to read
• is easier to write

than a single looped structure that performs the same logical operation.

Maybe I'll eat my words when you post a more concrete example, though.

 

[Troll-Brain]

Many textbooks caution readers not to use break and continue because it causes the execution flow to jump around. While this is certainly true, judicious use of break and continue can actually help make loops much more readable.

In other words, using break and continue is usually not recommended because humans are ... humans, the clearer, the better, less bug proof.
Now, here i suppose we need a better example (pseudo code) and then how it will be in jass.

 

[Adiktuz]

My example didn't show a case where it was actually needed, but I have run into structures where the complexity of what Is working with required a continue or nothing else. It is not always possible given an if/then statement.

@Adiktuz

A continue statement takes you to the top of a loop. My example had several ways out, but like I said the resources I've worked with sometimes have gotten into really complex if/then blocks and I'd wished for a continue statement. This example is very simple on purpose, but it's only for people who need it.

what I mean was that this:

loop
    loop
        //do stuff
        if condition then
            exitwhen true //continue
        endif
        //do stuff
        if loopIsDone then
            set exit=true
            exitwhen true
        endif
    endloop
    exitwhen exit
endloop

can just be

loop
    loop
        //do stuff
         exitwhen condition //continue
        //do stuff
        if loopIsDone then
            set exit=true
            exitwhen true
        endif
    endloop
    exitwhen exit
endloop

right? or is using the if faster?

 

[Arhowk]

loop
    loop
        //do stuff
         exitwhen condition //continue
        //do stuff
        if loopIsDone then
            set exit=true
            exitwhen true
        endif
    endloop
    exitwhen exit
endloop

one more opt set

loop
    loop
        //do stuff
        //do stuff
        exitwhen true 
    endloop
    exitwhen (standard conditions) or exit
endloop

I do agree that JASS code shouldn't need continue/break functions. After two years and 100k+ lines, never needed em once. (Use em all the time in Java but thats with string/file parsing)

 

[Adiktuz]

I don't see how that one is continue... Continue is used to skip any remaining actions for the current iteration and proceed to the next... so I don't see how putting exitwhen true at the end of the nested loop will achieve what Continue does...

 

[Arhowk]

I don't see how that one is continue...

if you want to "continue", just do exitwhen true (or exitwhen boolean)

 

[Magtheridon96]

exitwhen true is break.

 

[Arhowk]

exitwhen true is break.

no its just a do block emulation by putting exitwhen true at the end of a loop

 

[chobibo]

Normally you should not use break/continue ect...

Why not?

 

[Magtheridon96]

no its just a do block emulation by putting exitwhen true at the end of a loop

...
It's break.

 

[Arhowk]

...
It's break.

in a normal loop, yes.

 

[Magtheridon96]

How you use it is not important, it is technically the equivalent of break anywhere :v

 

[muzzel]

Yea well it does the same as break, but you dont really use it.

Using break only makes sense in combination with a condition, otherwise your loop always breaks, which isnt the point of a loop. So usually:

while(blabla) {
    if (something happens) {
        break;
    }
    bla bla bla..
}

You can do the same in jass:

loop
    if (something happens) then
        exitwhen true
    endif
    bla bla bla..
endloop

which however is equal to the much more convenient

loop
    exitwhen (something happens)
    bla bla bla..
endloop

So yea, its equal, but as the jass syntax for loops makes breaks unnecessary there is no point in using breaks .. i guess.

 

[Malhorne]

@Chobibro : Break/continue functions aren't recommended