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Part of TutorialFundamentals


Using a function, you can code it once and then call it when you need it, wherever you need it. The code demonstrates that you can assign the return value of a function to a variable. You may also use the return value of a function as an argument to another function (in this case squareIt(i) is evaluated in the for loop, and it's return value is passed to the writefln() function).


import std.stdio;

uint squareIt(uint x) 
    return x * x;

void main() 
    uint num = 10;
    writefln("%s squared is: %s\n", num, squareIt(num));
    num = squareIt(20);
    writefln("20 squared is: %s\n", num);
    for (int i = 0; i <= 5; i++)
        writefln("(%s * %s) == %s", i, i, squareIt(i));


Based on function.html by jcc7.