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The “Hello world” program is usually the first introduction to any programming language. It looks like this in the C programming language:
/* hello.c */
#import <stdio.h>
int main(int argc, char *argv[]) {
printf("Hello, world!");
return 0;
}
It demonstrates the minimum amount you need to write a C program. In more modern languages however, this example isn’t as useful anymore. Here’s the same example in Python:
# hello.py
print "Hello, world!"
A better hello world
In today’s world of more succint programming languages, we need a different “hello world” to demonstrate language features better. Here’s what I propose:
// hello.js
function getGreeting (name) {
return `Hello, ${name}!`
}
const message = getGreeting('world')
console.log(message)
This simple example demonstrates a few more things than printing strings:
- How to write a function with an argument
- Returning values from functions
- How to use variables
- The naming convention for functions (camelCase versus snake_case)
- String concatenation
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