import old itertools code

Author: make-github-pseudonymous-again

js/src/map/chain.js

@@ -0,0 +1,28 @@
+
+var chain = function ( iterables, out ) {
+
+	var i, j, n, len, it;
+
+	len = iterables.length;
+
+
+	if ( len === 0 ) {
+		return out;
+	}
+
+
+	for ( i = 0 ; i < len ; ++i ) {
+
+		it = iterables[i];
+		n = it.length;
+
+		for ( j = 0 ; j < n ; ++j ) {
+			out.push( it[j] );
+		}
+	}
+
+	return out;
+
+};
+
+exports.chain = chain;

js/src/map/combinations.js

@@ -0,0 +1,47 @@
+var combinations = function ( iterable, repeat, out ) {
+
+	// combinations('ABCD', 2) --> AB AC AD BC BD CD
+	// combinations(range(4), 3) --> 012 013 023 123
+
+	var pool, len, indices, i, j;
+
+	pool = iterable;
+	len = pool.length;
+
+	if ( repeat > len ) {
+		return out;
+	}
+
+	indices = range( 0, repeat, 1, [] );
+
+	out.push( pick( pool, indices, [] ) );
+
+	if ( repeat === 0 || len === 0 ) {
+		return out;
+	}
+
+	for ( ; ; ) {
+
+		for ( i = repeat - 1 ; i >= 0 ; --i ) {
+			if ( indices[i] !== i + len - repeat ) {
+				break;
+			}
+		}
+
+		if ( i < 0 ) {
+			return out;
+		}
+
+		++indices[i];
+
+		for ( j = i + 1 ; j < repeat ; ++j ) {
+			indices[j] = indices[j - 1] + 1;
+		}
+
+		out.push( pick( pool, indices, [] ) );
+
+	}
+
+};
+
+exports.combinations = combinations;

js/src/map/combinationswithrepetition.js

@@ -0,0 +1,42 @@
+
+
+var combinationswithrepetition = function ( iterable, r, out ) {
+
+	// combinationswithrepetition('ABC', 2) --> AA AB AC BB BC CC
+
+	var pool, len, indices, i, next;
+
+	pool = iterable;
+	len = pool.length;
+
+	if ( len === 0 && r > 0) {
+		return out;
+	}
+
+	indices = repeat( 0, r, [] );
+
+	out.push( pick( pool, indices, [] ) );
+
+	for ( ; ; ) {
+
+		for ( i = r - 1 ; i >= 0 ; --i ) {
+			if ( indices[i] !== len - 1 ) {
+				next = indices[i] + 1;
+				break;
+			}
+		}
+
+		if ( i < 0 ) {
+			return out;
+		}
+
+		for ( ; i < r ; ++i ) {
+			indices[i] = next;
+		}
+
+		out.push( pick( pool, indices, [] ) );
+	}
+
+};
+
+exports.combinationswithrepetition = combinationswithrepetition;

js/src/map/compress.js

@@ -0,0 +1,19 @@
+
+
+var compress = function ( iterable, selector, out ) {
+
+	var i, j;
+
+	j = Math.min( iterable.length, selector.length );
+
+	for ( i = 0 ; i < j ; ++i ) {
+		if ( selector[i] ) {
+			out.push( iterable[i] );
+		}
+	}
+
+	return out;
+
+};
+
+exports.compress = compress;

js/src/map/dropwhile.js

@@ -0,0 +1,35 @@
+
+var dropwhile = function ( predicate, iterable, out ) {
+
+	var i, n, e;
+
+	n = iterable.length;
+
+	if ( n === 0 ) {
+		return out;
+	}
+
+	i = 0;
+	e = iterable[i];
+
+	while ( predicate( e ) ) {
+		++i;
+
+		if ( i === n ) {
+			return out;
+		}
+
+		e = iterable[i];
+	}
+
+	out.push( e );
+
+	for ( ++i ; i < n ; ++i ) {
+		out.push( iterable[i] );
+	}
+
+	return out;
+
+};
+
+exports.dropwhile = dropwhile;

js/src/map/enumerate.js

@@ -0,0 +1,9 @@
+
+var enumerate = function ( iterable, out ) {
+
+	zip( [range( 0, iterable.length, 1, [] ), iterable], out );
+
+	return out;
+};
+
+exports.enumerate = enumerate;

js/src/map/filter.js

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+
+var filter = function ( predicate, iterable, out ) {
+
+	var i, len, item;
+
+	len = iterable.length;
+
+	for ( i = 0 ; i < len ; ++i ) {
+
+		item = iterable[i];
+
+		if ( predicate( item ) ) {
+			out.push( item );
+		}
+
+	}
+
+	return out;
+
+};
+
+exports.filter = filter;
+exports.filtertrue = filter;

js/src/map/filterfalse.js

@@ -0,0 +1,22 @@
+
+var filterfalse = function ( predicate, iterable, out ) {
+
+	var i, len, item;
+
+	len = iterable.length;
+
+	for ( i = 0 ; i < len ; ++i ) {
+
+		item = iterable[i];
+
+		if ( ! predicate( item ) ) {
+			out.push( item )
+		}
+
+	}
+
+	return out;
+
+};
+
+exports.filterfalse = filterfalse;

js/src/map/group.js

@@ -0,0 +1,46 @@
+
+var group = function ( key, iterable, out ) {
+
+	var i, len, curr, next, tuple, item, items;
+
+	len = iterable.length;
+
+	if ( len === 0 ) {
+		return out;
+	}
+
+	i = 0;
+	item = iterable[i];
+	next = key( item );
+
+	do {
+		curr = next;
+		items = [item];
+		tuple = [curr, items];
+
+		++i;
+
+		while ( i < len ) {
+
+			item = iterable[i];
+			next = key( item );
+
+			if ( next !== curr ) {
+				break;
+			}
+
+			items.push( item );
+			++i;
+		}
+
+		out.push( tuple );
+
+	} while ( i < len );
+
+
+	return out;
+
+};
+
+exports.group = group;
+exports.groupby = group;

js/src/map/map.js

@@ -0,0 +1,24 @@
+
+/**
+ *
+ * Maps a callable object over an array.
+ *
+ * /!\ currently only supports a (function, array) tuple as argument
+ *
+ */
+
+var map = function ( callable, iterable, out ) {
+
+	var i, len;
+
+	len = iterable.length;
+
+	for ( i = 0 ; i < len ; ++i ) {
+		out.push( callable( iterable[i] ) );
+	}
+
+	return out;
+
+};
+
+exports.map = map;