Source code in the jsish programming language

#!/usr/bin/env jsish
"use strict";

/* Twelve Days Of Christmas, in Jsish */
var days = [
    'first', 'second', 'third', 'fourth', 'fifth', 'sixth', 'seventh', 'eighth', 'ninth',
    'tenth', 'eleventh', 'twelfth'
];
 
var gifts = [
    "A partridge in a pear tree",
    "Two turtle doves",
    "Three french hens",
    "Four calling birds",
    "Five golden rings",
    "Six geese a-laying",
    "Seven swans a-swimming",
    "Eight maids a-milking",
    "Nine ladies dancing",
    "Ten lords a-leaping",
    "Eleven pipers piping",
    "Twelve drummers drumming"
];
 
var lines, verses = [], song;
 
for ( var i = 0; i < 12; i++ ) {
    lines = [];
    lines[0] = "On the " + days[i] + " day of Christmas, my true love gave to me";
 
    var j = i + 1;
    var k = 0;
    while ( j-- > 0 )
        lines[++k] = gifts[j];
 
    verses[i] = lines.join('\n');
 
    if ( i == 0 )
        gifts[0] = "And a partridge in a pear tree";
}
 
song = verses.join('\n\n');
;song;

/*
=!EXPECTSTART!=
song ==> On the first day of Christmas, my true love gave to me
A partridge in a pear tree

On the second day of Christmas, my true love gave to me
Two turtle doves
And a partridge in a pear tree

On the third day of Christmas, my true love gave to me
Three french hens
Two turtle doves
And a partridge in a pear tree

On the fourth day of Christmas, my true love gave to me
Four calling birds
Three french hens
Two turtle doves
And a partridge in a pear tree

On the fifth day of Christmas, my true love gave to me
Five golden rings
Four calling birds
Three french hens
Two turtle doves
And a partridge in a pear tree

On the sixth day of Christmas, my true love gave to me
Six geese a-laying
Five golden rings
Four calling birds
Three french hens
Two turtle doves
And a partridge in a pear tree

On the seventh day of Christmas, my true love gave to me
Seven swans a-swimming
Six geese a-laying
Five golden rings
Four calling birds
Three french hens
Two turtle doves
And a partridge in a pear tree

On the eighth day of Christmas, my true love gave to me
Eight maids a-milking
Seven swans a-swimming
Six geese a-laying
Five golden rings
Four calling birds
Three french hens
Two turtle doves
And a partridge in a pear tree

On the ninth day of Christmas, my true love gave to me
Nine ladies dancing
Eight maids a-milking
Seven swans a-swimming
Six geese a-laying
Five golden rings
Four calling birds
Three french hens
Two turtle doves
And a partridge in a pear tree

On the tenth day of Christmas, my true love gave to me
Ten lords a-leaping
Nine ladies dancing
Eight maids a-milking
Seven swans a-swimming
Six geese a-laying
Five golden rings
Four calling birds
Three french hens
Two turtle doves
And a partridge in a pear tree

On the eleventh day of Christmas, my true love gave to me
Eleven pipers piping
Ten lords a-leaping
Nine ladies dancing
Eight maids a-milking
Seven swans a-swimming
Six geese a-laying
Five golden rings
Four calling birds
Three french hens
Two turtle doves
And a partridge in a pear tree

On the twelfth day of Christmas, my true love gave to me
Twelve drummers drumming
Eleven pipers piping
Ten lords a-leaping
Nine ladies dancing
Eight maids a-milking
Seven swans a-swimming
Six geese a-laying
Five golden rings
Four calling birds
Three french hens
Two turtle doves
And a partridge in a pear tree
=!EXPECTEND!=
*/