ELSE IFs vs nested IF statements

Question

Hmm, I wonder if it's more efficient to use a bunch of ELSE IF statements or rather nested IFs (mainly in higher level programming langs). Did anyone here do any benchmarking? I would be really interested in the results. Thank you in advance for your answers. <3

Answer 1

Other languages formally support else if, but C and C++ only recognize it as an else clause with a nested if. Personally, I consider it borderline deceptive to format C/C++ code with apparent else if constructs; however, Brian Kernighan wrote in his book "Elements of Programming Style" that it is acceptable because it can make the code more readable. There is a point where multiple if/else statements might be made more efficient by revamping them into a switch/case statement, which can be faster due to use of a calculated jump instead of multiple test and branch instructions.

I will let others address else if for other languages. I would be mildly surprised if there is any difference though.

Answer 2

They don't give the same result. A if-else if chain does the same as a switch statement. Nested ifs test combinations of conditions.

Answer 3

I'm not talking about a SWITCH, just IF, ELSE IF and ELSE statements. The language doesn't matter.

Answer 4

Brian thanks for this! :)

Answer 5

its called a switch. what language?

Answer 6

That's what you use instead of a long if-elif chain. Again, called a switch. That's what you're describing.

Answer 7

Slick I know, but I asked for the benchmarking... Damn, why did I even bother to write the question.