hedgerow v1.0.3

hedgerow

hedgerow is a small library written in TypeScript for constructing polymorphic functions on constrained sequences of arguments. These sequences of arguments being referred to as hedges or hedge variables. This means all parameters have a range property and all functions on these parameters are functions on sequences of arrays. Refer to the documentation for further guidance and examples.

Installation

npm install hedgerow

A First Example:

import {Operator, PolymorphicOperator} from "hedgerow"

const con = new PolymorphicOperator();

con.implement(
  new Operator(
    new Parameter({
      in: "number", 
	  requires: n => n >= 0 && !(/[0-9]*\.[0-9]+/.test('' + n)),
	  range: -1}),
  (nums: number[], [sep]: string[]) => parseInt(nums.join(sep))));

con.implement(
  new Operator(
	[new Parameter("string"), 
	 new Parameter({in: "string", range: -1})],
	([sep]: string[], strs: string[]) => strs.join(sep)));

con.implement(
  new Operator(
	{requires: Array.isArray, range: -1},
	(objs: any[][]) => objs.flat()));

con.implement(
  new Operator(
    {in: Map, range: 2},
  ([l, r]: Map<any, any>[]) => 
    [...l.entries(), ...r.entries()]
	    .reduce((map, [k, v]) => map.set(k, v), new Map())));
	    
con([1,2,3,4]); //1234
con([" "], ["hello", "world"]); //'hello world'
con([[1, 2, 3], [4, 5, 6]]); //[1,2,3,4,5,6]
con([1.1, 2, 3, 4]); //Error no operator for arguments
con(["1", 2, 3, 4]); //Error no operator for arguments
con([{a: 1, b: 2}, {b: 3, c: 4}]); //Error: no operator for arguments

const [map1, map2] = [new Map(), new Map()];

map1.set("a", 1);
map1.set("b", 2);

map2.set("b", 3);
map2.set("c", 4);

con([map1, map2]); //Map(3) { 'a' => 1, 'b' => 3, 'c' => 4 }