objective c - Remove items in a for loop without side effects? -

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can remove items looping through in objective-c for loop without side effects?

for example, ok?

for (id item in items) {    if ( [item customcheck] ) {       [items removeobject:item];   // ok here? }

no, you'll error if mutate array while in fast enumeration loop. make copy of array, iterate on it, , remove original.

nsarray *itemscopy = [items copy];  (id item in itemscopy) {    if ( [item customcheck] )       [items removeobject:item];   // ok here }  [itemscopy release];

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