ios - What does @"//" do in childWithName and when to use it -

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i'm working on spritekit project , skspritenode has simple name:

node.name = @"cat"

however, when try [self childwithname:@"cat"], not retrieve object. through research noticed people mentioning should doing

[self childwithname:@"//cat"]

and works. wondering having "//" does?

it doesn't special things nsstrings, strings used search node tree, recursively searches of self's children.

from documentation:

when placed @ start of search string, [//] specifies search should begin @ root node , performed recursively across entire node tree. not legal anywhere else in search string.

so, example, let's have node tree:

                 scene               /         \              /           \         child1              child2        /      \              /     \       /        \            /        \ grandchild1  grandchild2 grandchild3  grandchild4

without //, childnodewithname: find child1 or child2. //, find child1, child2, grandchild1, grandchild2, grandchild3, or grandchild4.


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