>My assumption is the block of code between the FOR EACH (...) NEXT get compiled and executed in ASM or C while the code between the FOR (...)NEXT get compiled and executed in VFP. This would make the FOR EACH considerably fast when acting upon a grid with many columns OR a form with many controls - am I right?
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Nope - both are converted to the common p-code used by VFP - none of the VFP code is converted directly to machine language.