add functional js library... mmm, curry

This commit is contained in:
James B. Pollack 2015-10-26 16:28:18 -07:00
parent 5cf936f132
commit 88a312f992
2 changed files with 322 additions and 0 deletions

313
examples/libraries/fjs.js Normal file
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loadFJS = function(){
return fjs();
}
var fjs = function() {
"use strict";
var fjs = {},
hardReturn = "hardReturn;";
var lambda = function(exp) {
if (!fjs.isString(exp)) {
return;
}
var parts = exp.match(/(.*)\s*[=-]>\s*(.*)/);
parts.shift();
var params = parts.shift()
.replace(/^\s*|\s(?=\s)|\s*$|,/g, "").split(" ");
var body = parts.shift();
parts = ((!/\s*return\s+/.test(body)) ? "return " : "") + body;
params.push(parts);
return Function.apply({}, params);
};
var sliceArgs = function(args) {
return args.length > 0 ? [].slice.call(args, 0) : [];
};
fjs.isFunction = function(obj) {
return !!(obj && obj.constructor && obj.call && obj.apply);
};
fjs.isObject = function(obj) {
return fjs.isFunction(obj) || (!!obj && typeof(obj) === "object");
};
fjs.isArray = function(obj) {
return Object.prototype.toString.call(obj) === "[object Array]";
};
var checkFunction = function(func) {
if (!fjs.isFunction(func)) {
func = lambda(func);
if (!fjs.isFunction(func)) {
throw "fjs Error: Invalid function";
}
}
return func;
};
fjs.curry = function(func) {
func = checkFunction(func);
return function inner() {
var _args = sliceArgs(arguments);
if (_args.length === func.length) {
return func.apply(null, _args);
} else if (_args.length > func.length) {
var initial = func.apply(null, _args);
return fjs.fold(func, initial, _args.slice(func.length));
} else {
return function() {
var args = sliceArgs(arguments);
return inner.apply(null, _args.concat(args));
};
}
};
};
fjs.each = fjs.curry(function(iterator, items) {
iterator = checkFunction(iterator);
if (!fjs.exists(items) || !fjs.isArray(items)) {
return;
}
for (var i = 0; i < items.length; i += 1) {
if (iterator.call(null, items[i], i) === hardReturn) {
return;
}
}
});
fjs.map = fjs.curry(function(iterator, items) {
iterator = checkFunction(iterator);
var mapped = [];
fjs.each(function() {
mapped.push(iterator.apply(null, arguments));
}, items);
return mapped;
});
fjs.fold = fjs.foldl = fjs.curry(function(iterator, cumulate, items) {
iterator = checkFunction(iterator);
fjs.each(function(item, i) {
cumulate = iterator.call(null, cumulate, item, i);
}, items);
return cumulate;
});
fjs.reduce = fjs.reducel = fjs.foldll = fjs.curry(function(iterator, items) {
iterator = checkFunction(iterator);
var cumulate = items[0];
items.shift();
return fjs.fold(iterator, cumulate, items);
});
fjs.clone = function(items) {
var clone = [];
fjs.each(function(item) {
clone.push(item);
}, items);
return clone;
};
fjs.first = fjs.head = fjs.take = fjs.curry(function(iterator, items) {
iterator = checkFunction(iterator);
var first;
fjs.each(function(item) {
if (iterator.call(null, item)) {
first = item;
return hardReturn;
}
}, items);
return first;
});
fjs.rest = fjs.tail = fjs.drop = fjs.curry(function(iterator, items) {
var result = fjs.select(iterator, items);
result.shift();
return result;
});
fjs.last = fjs.curry(function(iterator, items) {
var itemsClone = fjs.clone(items);
return fjs.first(iterator, itemsClone.reverse());
});
fjs.every = fjs.all = fjs.curry(function(iterator, items) {
iterator = checkFunction(iterator);
var isEvery = true;
fjs.each(function(item) {
if (!iterator.call(null, item)) {
isEvery = false;
return hardReturn;
}
}, items);
return isEvery;
});
fjs.any = fjs.contains = fjs.curry(function(iterator, items) {
iterator = checkFunction(iterator);
var isAny = false;
fjs.each(function(item) {
if (iterator.call(null, item)) {
isAny = true;
return hardReturn;
}
}, items);
return isAny;
});
fjs.select = fjs.filter = fjs.curry(function(iterator, items) {
iterator = checkFunction(iterator);
var filtered = [];
fjs.each(function(item) {
if (iterator.call(null, item)) {
filtered.push(item);
}
}, items);
return filtered;
});
fjs.best = fjs.curry(function(iterator, items) {
iterator = checkFunction(iterator);
var compare = function(arg1, arg2) {
return iterator.call(this, arg1, arg2) ?
arg1 : arg2;
};
return fjs.reduce(compare, items);
});
fjs._while = fjs.curry(function(iterator, items) {
iterator = checkFunction(iterator);
var result = [];
fjs.each(function(item) {
if (iterator.call(null, item)) {
result.push(item);
} else {
return hardReturn;
}
}, items);
return result;
});
fjs.compose = function(funcs) {
var anyInvalid = fjs.any(function(func) {
return !fjs.isFunction(func);
});
funcs = sliceArgs(arguments).reverse();
if (anyInvalid(funcs)) {
throw "fjs Error: Invalid function to compose";
}
return function() {
var args = arguments;
var applyEach = fjs.each(function(func) {
args = [func.apply(null, args)];
});
applyEach(funcs);
return args[0];
};
};
fjs.partition = fjs.curry(function(iterator, items) {
iterator = checkFunction(iterator);
var truthy = [],
falsy = [];
fjs.each(function(item) {
(iterator.call(null, item) ? truthy : falsy).push(item);
}, items);
return [truthy, falsy];
});
fjs.group = fjs.curry(function(iterator, items) {
iterator = checkFunction(iterator);
var result = {};
var group;
fjs.each(function(item) {
group = iterator.call(null, item);
result[group] = result[group] || [];
result[group].push(item);
}, items);
return result;
});
fjs.shuffle = function(items) {
var j, t;
fjs.each(function(item, i) {
j = Math.floor(Math.random() * (i + 1));
t = items[i];
items[i] = items[j];
items[j] = t;
}, items);
return items;
};
fjs.toArray = function(obj) {
return fjs.map(function(key) {
return [key, obj[key]];
}, Object.keys(obj));
};
fjs.apply = fjs.curry(function(func, items) {
var args = [];
if (fjs.isArray(func)) {
args = [].slice.call(func, 1);
func = func[0];
}
return fjs.map(function(item) {
return item[func].apply(item, args);
}, items);
});
fjs.assign = fjs.extend = fjs.curry(function(obj1, obj2) {
fjs.each(function(key) {
obj2[key] = obj1[key];
}, Object.keys(obj1));
return obj2;
});
fjs.prop = function(prop) {
return function(obj) {
return obj[prop];
};
};
fjs.pluck = fjs.curry(function(prop, items) {
return fjs.map(fjs.prop(prop), items);
});
fjs.nub = fjs.unique = fjs.distinct = fjs.curry(function(comparator, items) {
var unique = items.length > 0 ? [items[0]] : [];
fjs.each(function(item) {
if (!fjs.any(fjs.curry(comparator)(item), unique)) {
unique[unique.length] = item;
}
}, items);
return unique;
});
fjs.exists = function(obj) {
return obj != null; // jshint ignore:line
};
fjs.truthy = function(obj) {
return fjs.exists(obj) && obj !== false;
};
fjs.falsy = function(obj) {
return !fjs.truthy(obj);
};
fjs.each(function(type) {
fjs["is" + type] = function(obj) {
return Object.prototype.toString.call(obj) === "[object " + type + "]";
};
}, ["Arguments", "Date", "Number", "RegExp", "String"]);
return fjs;
}

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Script.include('fjs.js');
var fjs = loadFJS();
var concatenate = fjs.curry(function(word1, word2) {
return word1 + " " + word2;
});
var concatenateHello = concatenate("Hello");
var hi = concatenateHello("World");
print('anyone listenig?' + hi)