minisweeper_source.js

// helper function for counting the number of adjacent mines
// This is a function of one argument that returns a function of one argument
// This is actually an interesting syntax to make curryable functions in javascript
f=i=>x=>s+=(c[i+x]|0)+(c[i-x]|0);
// board size
// The board is actually one column wider to prevent edge wrapping
// this variable will be used to know how many fields should be cleared before you won
m=256;
for(i=272;i--;)
	// there is some undocumented browser behaviour that makes the id of an element a variable in javascript
	// (at least, I coudn't find documentation)
	// the variable refers to the element
	// since we have this objects, and numbers can be properties of an object, this object also holds the main game field
	c.innerHTML += i%17 ?
		// for every tile not on the invisible border
		`<a onclick=event.target.outerHTML=c[i=${
			// set whether a mine is there
			// random takes no arguments, so that's a good place to put an unrelated expression
			// decrease m for every mine
			m -=c[i]=Math.random(a=alert)<.2, 
			i // and return the index
		// when clicked and it is a mine, explode
		// when it is not a mine fill in the number
		// the indices of adjacent tiles are -18, -17, -16, -1, 1, 16, 17, 18
		// the function f takes care of the negatives
		// again, f is a curried function so f(i) returns a function of one argument
		// decrease m (number of tiles left to clear) and if it is 0 then you won
		}]?(a("BOOM"),"X"):[1,16,17,18].map(f(i),s=0,--m||a("=D"))|s>#</a> `
		:
		// the invisible border is drawn as a newline
		`
`