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- /*
- MIT License http://www.opensource.org/licenses/mit-license.php
- Author Mikola Lysenko @mikolalysenko
- */
- "use strict";
- /* cspell:disable-next-line */
- // Refactor: Peter Somogyvari @petermetz
- const compileSearch = (funcName, predicate, reversed, extraArgs, earlyOut) => {
- const code = [
- "function ",
- funcName,
- "(a,l,h,",
- extraArgs.join(","),
- "){",
- earlyOut ? "" : "var i=",
- reversed ? "l-1" : "h+1",
- ";while(l<=h){var m=(l+h)>>>1,x=a[m]"
- ];
- if (earlyOut) {
- if (predicate.indexOf("c") < 0) {
- code.push(";if(x===y){return m}else if(x<=y){");
- } else {
- code.push(";var p=c(x,y);if(p===0){return m}else if(p<=0){");
- }
- } else {
- code.push(";if(", predicate, "){i=m;");
- }
- if (reversed) {
- code.push("l=m+1}else{h=m-1}");
- } else {
- code.push("h=m-1}else{l=m+1}");
- }
- code.push("}");
- if (earlyOut) {
- code.push("return -1};");
- } else {
- code.push("return i};");
- }
- return code.join("");
- };
- const compileBoundsSearch = (predicate, reversed, suffix, earlyOut) => {
- const arg1 = compileSearch(
- "A",
- "x" + predicate + "y",
- reversed,
- ["y"],
- earlyOut
- );
- const arg2 = compileSearch(
- "P",
- "c(x,y)" + predicate + "0",
- reversed,
- ["y", "c"],
- earlyOut
- );
- const fnHeader = "function dispatchBinarySearch";
- const fnBody =
- "(a,y,c,l,h){\
- if(typeof(c)==='function'){\
- return P(a,(l===void 0)?0:l|0,(h===void 0)?a.length-1:h|0,y,c)\
- }else{\
- return A(a,(c===void 0)?0:c|0,(l===void 0)?a.length-1:l|0,y)\
- }}\
- return dispatchBinarySearch";
- const fnArgList = [arg1, arg2, fnHeader, suffix, fnBody, suffix];
- const fnSource = fnArgList.join("");
- const result = new Function(fnSource);
- return result();
- };
- module.exports = {
- ge: compileBoundsSearch(">=", false, "GE"),
- gt: compileBoundsSearch(">", false, "GT"),
- lt: compileBoundsSearch("<", true, "LT"),
- le: compileBoundsSearch("<=", true, "LE"),
- eq: compileBoundsSearch("-", true, "EQ", true)
- };
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