What happens when I try to create an object using its empty default constructor but while adding brackets in ANSI C++?

Question

I have a class called "Complex" which is intended to represent complex numbers. I have defined an empty default constructor for the class that only prints a message to the screen. When I try to create an object of the class in the main function as follows:

Complex c1();

The compiler(I am using BorlandC) doesn't give a syntax error but it doesn't create the object. How does the compiler interpret this line?

It is a function declaration, not an object construction. – Evg Nov 20 '18 at 11:22 — Evg, Nov 20 '18 at 11:22

score 4 · Accepted Answer · answered Nov 20 '18 at 11:24

4

When you write this:

int foo();

…it declares a function called foo that returns an int.

When you write this:

Complex c1();

…it declares a function called c1 that returns a Complex.

Lose the ().

Contrary to popular belief, this is not quite "the most vexing parse", but it is close.

answered Nov 20 '18 at 11:24

Lightness Races in Orbit

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As a curious follow-up question can you mention what you consider as "the most vexing parse"? :) – Islam Hassan Nov 20 '18 at 11:38
2

@IslamEl-Rougy `Complex c1(Complex(arg))` also declares a function. [Read more on Wikipedia](https://en.wikipedia.org/wiki/Most_vexing_parse). – Lightness Races in Orbit Nov 20 '18 at 11:44
*Second most* vexing parse? – StoryTeller - Unslander Monica Nov 20 '18 at 11:48

What happens when I try to create an object using its empty default constructor but while adding brackets in ANSI C++?

1 Answers1