What is Pointer Rewiring aka Relinking?
Since a “pointer” is a much-feared word, let’s clarify what is pointer rewiring/relinking. That is the idiom used to speed up nontrivial types of moving. You do not move them, you swap their internals.
Let’s visualize this function
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// overload for pointers to int inline void rewire( int * A, int * B ) { int * temp = A ; A = B ; B = temp ; } |
Watch carefully.
That is the situation upon entering the rewiring function. Then:
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T * temp = a ; |
And then this:
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a = b |
This is where “pointer to A” loses its address. It is rewired to the same value as pointer B. Lastly:
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b = temp; |
Now B is rewired to the “value A”. Effectively pointers A and B have exchanged addresses of the values they have been pointing to. The pointers themselves have changed. They have been “rewired”.