Aug 22, 2014 · Note that there is an #elif construct in the "preprocessor" syntax. Note also that C, C++ and ECMAScript - and I am sure many more C-like languages - also have the property that there is no formal "else if" statement. Rather, in each the behaviour falls out of the definition of "else" as coming before a single statement.

May 4, 2016 · As @anatolyg noted this is why you have a #elif in C macro language. Cobol-85 has a different take on the elseif statement. It provides an extended Select / case statement.

Apr 13, 2017 · It is precisely this problem, known as the "dangling ELSE" problem and first seen in PASCAL (or possibly ALGOL), long before C was developed, that caused Jean Ichbiah and his team to adopt the fully-bracketed style for control structures in Ada. –

Jun 27, 2017 · I just uncovered in IAR Embedded Workbench for MSP430, v7.11.1, which reports icc430 --version as "IAR C/C++ Compiler V7.11.1.983/W32 for MSP430", that #elseif compiles without error, but does NOT evaluate the same as #elif.

Jan 10, 2015 · The condition that follows #if or #elif can only evaluate constant expressions, including macro expressions. For example: For example: #if TABLE_SIZE > 200 #undef TABLE_SIZE #define TABLE_SIZE 200 #elif TABLE_SIZE < 50 #undef TABLE_SIZE #define TABLE_SIZE 50 #else #undef TABLE_SIZE #define TABLE_SIZE 100 #endif int table[TABLE_SIZE];

Mar 30, 2021 · To define elif to be replaced by else if, simply use: #define elif else if That said, this would generally be regarded as a bad idea. C programmers become accustomed to the normal keywords that affect program control, and using customized keywords will confuse many people.

@jdi Though conditional-expressions may not be to your taste, they were specifically designed to handle if-elif-elif-else chains, just as the OP requested. They aren't hard to learn and can gracefully handle situations that aren't as amenable to dictionary lookup logic: 'A' if grade>=90 else 'B' if grade>=80 else 'C' if grade>=70 else 'F'.

Without "elseif" syntax you would have to write chain if-statements for processing one of several possible outcomes this way:

Oct 31, 2017 · @RemyLebeau Yes, we can use #ifdef with #elif. But, If we #define macro with value 0 for #ifdef case, the #ifdef case tests it to true. Otherwise, if we #define macro with value 0 for #elif case, the #elif case test it to false. – rosshjb …

Jul 14, 2016 · I can't seem to get #elifdef to work in my iOS project. If I do this: #ifdef X const Foo bar[] = { ... }; #else const Foo bar[] = { ,,, }; #endif Then the top one (under X) gets highlighted and ...