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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)
};