Title here
Summary here
Functions are central in D. We’ll learn about functions with a few different examples.
import std.stdio;
// Here's a function that takes two ints and returns
// their sum as an int.
int plus(int a, int b) {
// D requires explicit returns, i.e. it won't
// automatically return the value of the last
// expression.
return a + b;
}
// When you have multiple consecutive parameters of
// the same type, you can omit the type name for the
// like-typed parameters up to the final parameter that
// declares the type.
int plusPlus(int a, b, c) {
return a + b + c;
}
void main() {
// Call a function just as you'd expect, with
// name(args).
int res = plus(1, 2);
writeln("1+2 = ", res);
res = plusPlus(1, 2, 3);
writeln("1+2+3 = ", res);
}
To run the program, save it as functions.d
and use the D compiler:
$ dmd -run functions.d
1+2 = 3
1+2+3 = 6
There are several other features to D functions. One is multiple return values, which we’ll look at next.