#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <assert.h>

union Number {
    int as_int;
    double as_double;
    char as_char;
};

enum NumberType {
    INT,
    DOUBLE,
    CHAR
};  // remember the semicolon
// Declare an enum type with three values: INT (=0), DOUBLE (=1), CHAR (=2).
// Stored internally as an int.
// Values are automatically numbered starting with 0.
// Value are guaranteed to be distinct.
// Values can be referred to directly, without every making an instance of the enum type.

void print_number(union Number n, int which) {  // Better but still kinda bad!  Use enum.
    if(which == INT) {
        printf("%d\n", n.as_int);
    }
    else if(which == DOUBLE) {
        printf("%f\n", n.as_double);
    }
    else if(which == CHAR) {
        printf("'%c'\n", n.as_char);
    }
}
int main(int argc, char* argv[]) {
    union Number n = { .as_double = 3.1415962 };
    print_number(n, DOUBLE);
    return EXIT_SUCCESS;
}

// double is like a float but twice the precision

/* vim: set tabstop=4 shiftwidth=4 fileencoding=utf-8 noexpandtab: */