Why Can't I Use Parentheses in my Constructor Declaration Without Arguments?

A Perplexing Parse Error: Unraveling the Conundrum of Parentheses in Constructor Arguments

When encountering the cryptic error message "request for member 'function1' in 'myObj', which is of non-class type 'MyClass ()()'" while attempting to compile a C program, developers may find themselves pondering the reasons behind this perplexing parse error. The source code in question contains a class with a constructor lacking any arguments, declared using the following line:

MyClass myObj();

Upon executing the compilation process, the aforementioned error surfaces, indicating that the member function 'function1' cannot be accessed via the object 'myObj' because 'myObj' is perceived as a non-class type. To resolve this issue, the code is modified to:

MyClass myObj;

This raises the question of whether the absence of arguments in a constructor declaration necessitates the omission of parentheses. While empty constructor declarations using parentheses have been used previously in C , the language standard has taken a decisive stance: ambiguities like the one in the provided code are consistently resolved in favor of function declarations.

It is crucial to note that empty parentheses initializers are permissible in certain scenarios, such as within new expressions or while constructing a value-initialized temporary object. However, in the case of constructor declarations with no arguments, the standard adamantly dictates the omission of parentheses. This ensures clarity and prevents potential confusions that may arise from syntactic ambiguities.

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