Benchmark: Array element assignment

Array element assignment (version: 3)

Replace the content of one array with the content of another array. Assume that: • alternative approaches are not a choice: • reusing the second array; • cloning the second array; • the arrays are not the same, are not sparse and are of the same length; • content order must be kept; • the difference between +0 and -0 and the differences between NaNs are irrelevant: • we can use === or Object.is() to avoid assignments; • otherwise, elements are opaque; The tests with literals, constants and variables serve as baselines for performance comparison.

Comparing performance of: Do nothing at the beginning, cold hardware vs Constant binding to literal vs Constant binding to constant vs Constant binding to variable vs Constant binding to array vs Constant reverse binding to array vs Variable binding to literal vs Variable binding to constant vs Variable binding to variable vs Variable binding to array vs Variable reverse binding to array vs Variable assignment to literal vs Variable assignment to constant vs Variable assignment to variable vs Variable assignment to array vs Variable reverse assignment to array vs Array assignment to literal vs Array reverse assignment to literal vs Array assignment to constant vs Array reverse assignment to constant vs Array assignment to variable vs Array reverse assignment to variable vs Array assignment to array vs Array reverse assignment to array vs Conditional variable assignment to literal !== vs Conditional variable assignment to constant !== vs Conditional variable assignment to variable !== vs Conditional variable assignment to array !== vs Conditional variable reverse assignment to array !== vs Conditional array assignment to literal !== vs Conditional array reverse assignment to literal !== vs Conditional array assignment to constant !== vs Conditional array reverse assignment to constant !== vs Conditional array assignment to variable !== vs Conditional array reverse assignment to variable !== vs Conditional array assignment to array !== vs Conditional array reverse assignment to array !== vs Conditional variable assignment to literal Object.is() vs Conditional variable assignment to constant Object.is() vs Conditional variable assignment to variable Object.is() vs Conditional variable assignment to array Object.is() vs Conditional variable reverse assignment to array Object.is() vs Conditional array assignment to literal Object.is() vs Conditional array reverse assignment to literal Object.is() vs Conditional array assignment to constant Object.is() vs Conditional array reverse assignment to constant Object.is() vs Conditional array assignment to variable Object.is() vs Conditional array reverse assignment to variable Object.is() vs Conditional array assignment to array Object.is() vs Conditional array reverse assignment to array Object.is() vs Loop from start with literal length vs Loop from end with literal length vs Loop from start with constant length vs Loop from end with constant length vs Loop from start with constant first length vs Loop from end with constant first length vs Loop from start with constant second length vs Loop from end with constant second length vs Loop from start with variable first length vs Loop from end with variable first length vs Loop from start with variable second length vs Loop from end with variable second length vs Loop from start re-evaluating first length vs Loop from end evaluating first length vs Loop from start re-evaluating second length vs Loop from end evaluating second length vs Loop in first vs Loop in second vs Loop of first vs Loop of second vs .forEach() on first vs .forEach() on first closure vs .forEach() on second vs .forEach() on second closure vs Array-destructuring constant binding vs Array-destructuring variable binding vs Array-destructuring variable assignment vs Array-destructuring element assignment vs Array-destructuring rest assignment vs Object-destructuring constant binding with numbers vs Object-destructuring reverse constant binding with numbers vs Object-destructuring variable binding with numbers vs Object-destructuring reverse variable binding with numbers vs Object-destructuring variable assignment with numbers vs Object-destructuring reverse variable assignment with numbers vs Object-destructuring element assignment with numbers vs Object-destructuring reverse element assignment with numbers vs Object-destructuring constant binding with strings vs Object-destructuring reverse constant binding with strings vs Object-destructuring variable binding with strings vs Object-destructuring reverse variable binding with strings vs Object-destructuring variable assignment with strings vs Object-destructuring reverse variable assignment with strings vs Object-destructuring element assignment with strings vs Object-destructuring reverse element assignment with strings vs Object-destructuring rest assignment vs Object.assign() vs Do nothing at the end, warm hardware

Created: 5 months ago by: Registered User

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Script Preparation code:

const X = "x", Y = "y", Z = "z", W = "d";
let   a = "a", b = "b", c = "c", d = "d";
let   x = "x", y = "y", z = "z", w = "d";
const firstArray  = [ "a", "b", "c", "d" ];
let   firstArray2 = [ "a", "b", "c", "d" ]; // for destructuring rest assignment tests
const secondArray = [ "x", "y", "z", "d" ];

AخA
 
const X = "x", Y = "y", Z = "z", W = "d";let   a = "a", b = "b", c = "c", d = "d";let   x = "x", y = "y", z = "z", w = "d";const firstArray  = [ "a", "b", "c", "d" ];let   firstArray2 = [ "a", "b", "c", "d" ]; // for destructuring rest assignment testsconst secondArray = [ "x", "y", "z", "d" ];

Tests:

Do nothing at the beginning, cold hardware
;
;
Constant binding to literal
const first0 = "x"; const first1 = "y"; const first2 = "z"; const first3 = "d";
const first0 = "x";
const first1 = "y";
const first2 = "z";
const first3 = "d";
Constant binding to constant
const first0 = X; const first1 = Y; const first2 = Z; const first3 = W;
const first0 = X;
const first1 = Y;
const first2 = Z;
const first3 = W;
Constant binding to variable
const first0 = x; const first1 = y; const first2 = z; const first3 = w;
const first0 = x;
const first1 = y;
const first2 = z;
const first3 = w;
Constant binding to array
const first0 = secondArray[0]; const first1 = secondArray[1]; const first2 = secondArray[2]; const first3 = secondArray[3];
const first0 = secondArray[0];
const first1 = secondArray[1];
const first2 = secondArray[2];
const first3 = secondArray[3];
Constant reverse binding to array
const first3 = secondArray[3]; const first2 = secondArray[2]; const first1 = secondArray[1]; const first0 = secondArray[0];
const first3 = secondArray[3];
const first2 = secondArray[2];
const first1 = secondArray[1];
const first0 = secondArray[0];
Variable binding to literal
let first0 = "x"; let first1 = "y"; let first2 = "z"; let first3 = "d";
let first0 = "x";
let first1 = "y";
let first2 = "z";
let first3 = "d";
Variable binding to constant
let first0 = X; let first1 = Y; let first2 = Z; let first3 = W;
let first0 = X;
let first1 = Y;
let first2 = Z;
let first3 = W;
Variable binding to variable
let first0 = x; let first1 = y; let first2 = z; let first3 = w;
let first0 = x;
let first1 = y;
let first2 = z;
let first3 = w;
Variable binding to array
let first0 = secondArray[0]; let first1 = secondArray[1]; let first2 = secondArray[2]; let first3 = secondArray[3];
let first0 = secondArray[0];
let first1 = secondArray[1];
let first2 = secondArray[2];
let first3 = secondArray[3];
Variable reverse binding to array
let first3 = secondArray[3]; let first2 = secondArray[2]; let first1 = secondArray[1]; let first0 = secondArray[0];
let first3 = secondArray[3];
let first2 = secondArray[2];
let first1 = secondArray[1];
let first0 = secondArray[0];
Variable assignment to literal
a = "x"; b = "y"; c = "z"; d = "d";
a = "x";
b = "y";
c = "z";
d = "d";
Variable assignment to constant
a = X; b = Y; c = Z; d = W;
a = X;
b = Y;
c = Z;
d = W;
Variable assignment to variable
a = x; b = y; c = z; d = w;
a = x;
b = y;
c = z;
d = w;
Variable assignment to array
a = secondArray[0]; b = secondArray[1]; c = secondArray[2]; d = secondArray[3];
a = secondArray[0];
b = secondArray[1];
c = secondArray[2];
d = secondArray[3];
Variable reverse assignment to array
d = secondArray[3]; c = secondArray[2]; b = secondArray[1]; a = secondArray[0];
d = secondArray[3];
c = secondArray[2];
b = secondArray[1];
a = secondArray[0];
Array assignment to literal
firstArray[0] = "x"; firstArray[1] = "y"; firstArray[2] = "z"; firstArray[3] = "d";
firstArray[0] = "x";
firstArray[1] = "y";
firstArray[2] = "z";
firstArray[3] = "d";
Array reverse assignment to literal
firstArray[3] = "d"; firstArray[2] = "z"; firstArray[1] = "y"; firstArray[0] = "x";
firstArray[3] = "d";
firstArray[2] = "z";
firstArray[1] = "y";
firstArray[0] = "x";
Array assignment to constant
firstArray[0] = X; firstArray[1] = Y; firstArray[2] = Z; firstArray[3] = W;
firstArray[0] = X;
firstArray[1] = Y;
firstArray[2] = Z;
firstArray[3] = W;
Array reverse assignment to constant
firstArray[3] = W; firstArray[2] = Z; firstArray[1] = Y; firstArray[0] = X;
firstArray[3] = W;
firstArray[2] = Z;
firstArray[1] = Y;
firstArray[0] = X;
Array assignment to variable
firstArray[0] = x; firstArray[1] = y; firstArray[2] = z; firstArray[3] = w;
firstArray[0] = x;
firstArray[1] = y;
firstArray[2] = z;
firstArray[3] = w;
Array reverse assignment to variable
firstArray[3] = w; firstArray[2] = z; firstArray[1] = y; firstArray[0] = x;
firstArray[3] = w;
firstArray[2] = z;
firstArray[1] = y;
firstArray[0] = x;
Array assignment to array
firstArray[0] = secondArray[0]; firstArray[1] = secondArray[1]; firstArray[2] = secondArray[2]; firstArray[3] = secondArray[3];
firstArray[0] = secondArray[0];
firstArray[1] = secondArray[1];
firstArray[2] = secondArray[2];
firstArray[3] = secondArray[3];
Array reverse assignment to array
firstArray[3] = secondArray[3]; firstArray[2] = secondArray[2]; firstArray[1] = secondArray[1]; firstArray[0] = secondArray[0];
firstArray[3] = secondArray[3];
firstArray[2] = secondArray[2];
firstArray[1] = secondArray[1];
firstArray[0] = secondArray[0];
Conditional variable assignment to literal !==
if (a !== "x") a = "x"; if (b !== "y") b = "y"; if (c !== "z") c = "z"; if (d !== "d") d = "d";
if (a !== "x") a = "x";
if (b !== "y") b = "y";
if (c !== "z") c = "z";
if (d !== "d") d = "d";
Conditional variable assignment to constant !==
if (a !== X) a = X; if (b !== Y) b = Y; if (c !== Z) c = Z; if (d !== W) d = W;
if (a !== X) a = X;
if (b !== Y) b = Y;
if (c !== Z) c = Z;
if (d !== W) d = W;
Conditional variable assignment to variable !==
if (a !== x) a = x; if (b !== y) b = y; if (c !== z) c = z; if (d !== w) d = w;
if (a !== x) a = x;
if (b !== y) b = y;
if (c !== z) c = z;
if (d !== w) d = w;
Conditional variable assignment to array !==
const second0 = secondArray[0]; const second1 = secondArray[1]; const second2 = secondArray[2]; const second3 = secondArray[3]; if (a !== second0) a = second0; if (b !== second1) b = second1; if (c !== second2) c = second2; if (d !== second3) d = second3;
const second0 = secondArray[0];
const second1 = secondArray[1];
const second2 = secondArray[2];
const second3 = secondArray[3];
if (a !== second0) a = second0;
if (b !== second1) b = second1;
if (c !== second2) c = second2;
if (d !== second3) d = second3;
Conditional variable reverse assignment to array !==
const second3 = secondArray[3]; const second2 = secondArray[2]; const second1 = secondArray[1]; const second0 = secondArray[0]; if (d !== second3) d = second3; if (c !== second2) c = second2; if (b !== second1) b = second1; if (a !== second0) a = second0;
const second3 = secondArray[3];
const second2 = secondArray[2];
const second1 = secondArray[1];
const second0 = secondArray[0];
if (d !== second3) d = second3;
if (c !== second2) c = second2;
if (b !== second1) b = second1;
if (a !== second0) a = second0;
Conditional array assignment to literal !==
if (firstArray[0] !== "x") firstArray[0] = "x"; if (firstArray[1] !== "y") firstArray[1] = "y"; if (firstArray[2] !== "z") firstArray[2] = "z"; if (firstArray[3] !== "d") firstArray[3] = "d";
if (firstArray[0] !== "x") firstArray[0] = "x";
if (firstArray[1] !== "y") firstArray[1] = "y";
if (firstArray[2] !== "z") firstArray[2] = "z";
if (firstArray[3] !== "d") firstArray[3] = "d";
Conditional array reverse assignment to literal !==
if (firstArray[3] !== "d") firstArray[3] = "d"; if (firstArray[2] !== "z") firstArray[2] = "z"; if (firstArray[1] !== "y") firstArray[1] = "y"; if (firstArray[0] !== "x") firstArray[0] = "x";
if (firstArray[3] !== "d") firstArray[3] = "d";
if (firstArray[2] !== "z") firstArray[2] = "z";
if (firstArray[1] !== "y") firstArray[1] = "y";
if (firstArray[0] !== "x") firstArray[0] = "x";
Conditional array assignment to constant !==
if (firstArray[0] !== X) firstArray[0] = X; if (firstArray[1] !== Y) firstArray[1] = Y; if (firstArray[2] !== Z) firstArray[2] = Z; if (firstArray[3] !== W) firstArray[3] = W;
if (firstArray[0] !== X) firstArray[0] = X;
if (firstArray[1] !== Y) firstArray[1] = Y;
if (firstArray[2] !== Z) firstArray[2] = Z;
if (firstArray[3] !== W) firstArray[3] = W;
Conditional array reverse assignment to constant !==
if (firstArray[3] !== W) firstArray[3] = W; if (firstArray[2] !== Z) firstArray[2] = Z; if (firstArray[1] !== Y) firstArray[1] = Y; if (firstArray[0] !== X) firstArray[0] = X;
if (firstArray[3] !== W) firstArray[3] = W;
if (firstArray[2] !== Z) firstArray[2] = Z;
if (firstArray[1] !== Y) firstArray[1] = Y;
if (firstArray[0] !== X) firstArray[0] = X;
Conditional array assignment to variable !==
if (firstArray[0] !== x) firstArray[0] = x; if (firstArray[1] !== y) firstArray[1] = y; if (firstArray[2] !== z) firstArray[2] = z; if (firstArray[3] !== w) firstArray[3] = w;
if (firstArray[0] !== x) firstArray[0] = x;
if (firstArray[1] !== y) firstArray[1] = y;
if (firstArray[2] !== z) firstArray[2] = z;
if (firstArray[3] !== w) firstArray[3] = w;
Conditional array reverse assignment to variable !==
if (firstArray[3] !== w) firstArray[3] = w; if (firstArray[2] !== z) firstArray[2] = z; if (firstArray[1] !== y) firstArray[1] = y; if (firstArray[0] !== x) firstArray[0] = x;
if (firstArray[3] !== w) firstArray[3] = w;
if (firstArray[2] !== z) firstArray[2] = z;
if (firstArray[1] !== y) firstArray[1] = y;
if (firstArray[0] !== x) firstArray[0] = x;
Conditional array assignment to array !==
const second0 = secondArray[0]; const second1 = secondArray[1]; const second2 = secondArray[2]; const second3 = secondArray[3]; if (firstArray[0] !== second0) firstArray[0] = second0; if (firstArray[1] !== second1) firstArray[1] = second1; if (firstArray[2] !== second2) firstArray[2] = second2; if (firstArray[3] !== second3) firstArray[3] = second3;
const second0 = secondArray[0];
const second1 = secondArray[1];
const second2 = secondArray[2];
const second3 = secondArray[3];
if (firstArray[0] !== second0) firstArray[0] = second0;
if (firstArray[1] !== second1) firstArray[1] = second1;
if (firstArray[2] !== second2) firstArray[2] = second2;
if (firstArray[3] !== second3) firstArray[3] = second3;
Conditional array reverse assignment to array !==
const second3 = secondArray[3]; const second2 = secondArray[2]; const second1 = secondArray[1]; const second0 = secondArray[0]; if (firstArray[3] !== second3) firstArray[3] = second3; if (firstArray[2] !== second2) firstArray[2] = second2; if (firstArray[1] !== second1) firstArray[1] = second1; if (firstArray[0] !== second0) firstArray[0] = second0;
const second3 = secondArray[3];
const second2 = secondArray[2];
const second1 = secondArray[1];
const second0 = secondArray[0];
if (firstArray[3] !== second3) firstArray[3] = second3;
if (firstArray[2] !== second2) firstArray[2] = second2;
if (firstArray[1] !== second1) firstArray[1] = second1;
if (firstArray[0] !== second0) firstArray[0] = second0;
Conditional variable assignment to literal Object.is()
if (!Object.is(a, "x")) a = "x"; if (!Object.is(b, "y")) b = "y"; if (!Object.is(c, "z")) c = "z"; if (!Object.is(d, "d")) d = "d";
if (!Object.is(a, "x")) a = "x";
if (!Object.is(b, "y")) b = "y";
if (!Object.is(c, "z")) c = "z";
if (!Object.is(d, "d")) d = "d";
Conditional variable assignment to constant Object.is()
if (!Object.is(a, X)) a = X; if (!Object.is(b, Y)) b = Y; if (!Object.is(c, Z)) c = Z; if (!Object.is(d, W)) d = W;
if (!Object.is(a, X)) a = X;
if (!Object.is(b, Y)) b = Y;
if (!Object.is(c, Z)) c = Z;
if (!Object.is(d, W)) d = W;
Conditional variable assignment to variable Object.is()
if (!Object.is(a, x)) a = x; if (!Object.is(b, y)) b = y; if (!Object.is(c, z)) c = z; if (!Object.is(d, w)) d = w;
if (!Object.is(a, x)) a = x;
if (!Object.is(b, y)) b = y;
if (!Object.is(c, z)) c = z;
if (!Object.is(d, w)) d = w;
Conditional variable assignment to array Object.is()
const second0 = secondArray[0]; const second1 = secondArray[1]; const second2 = secondArray[2]; const second3 = secondArray[3]; if (!Object.is(a, second0)) a = second0; if (!Object.is(b, second1)) b = second1; if (!Object.is(c, second2)) c = second2; if (!Object.is(d, second3)) d = second3;
const second0 = secondArray[0];
const second1 = secondArray[1];
const second2 = secondArray[2];
const second3 = secondArray[3];
if (!Object.is(a, second0)) a = second0;
if (!Object.is(b, second1)) b = second1;
if (!Object.is(c, second2)) c = second2;
if (!Object.is(d, second3)) d = second3;
Conditional variable reverse assignment to array Object.is()
const second3 = secondArray[3]; const second2 = secondArray[2]; const second1 = secondArray[1]; const second0 = secondArray[0]; if (!Object.is(d, second3)) d = second3; if (!Object.is(c, second2)) c = second2; if (!Object.is(b, second1)) b = second1; if (!Object.is(a, second0)) a = second0;
const second3 = secondArray[3];
const second2 = secondArray[2];
const second1 = secondArray[1];
const second0 = secondArray[0];
if (!Object.is(d, second3)) d = second3;
if (!Object.is(c, second2)) c = second2;
if (!Object.is(b, second1)) b = second1;
if (!Object.is(a, second0)) a = second0;
Conditional array assignment to literal Object.is()
if (!Object.is(firstArray[0], "x")) firstArray[0] = "x"; if (!Object.is(firstArray[1], "y")) firstArray[1] = "y"; if (!Object.is(firstArray[2], "z")) firstArray[2] = "z"; if (!Object.is(firstArray[3], "d")) firstArray[3] = "d";
if (!Object.is(firstArray[0], "x")) firstArray[0] = "x";
if (!Object.is(firstArray[1], "y")) firstArray[1] = "y";
if (!Object.is(firstArray[2], "z")) firstArray[2] = "z";
if (!Object.is(firstArray[3], "d")) firstArray[3] = "d";
Conditional array reverse assignment to literal Object.is()
if (!Object.is(firstArray[3], "d")) firstArray[3] = "d"; if (!Object.is(firstArray[2], "z")) firstArray[2] = "z"; if (!Object.is(firstArray[1], "y")) firstArray[1] = "y"; if (!Object.is(firstArray[0], "x")) firstArray[0] = "x";
if (!Object.is(firstArray[3], "d")) firstArray[3] = "d";
if (!Object.is(firstArray[2], "z")) firstArray[2] = "z";
if (!Object.is(firstArray[1], "y")) firstArray[1] = "y";
if (!Object.is(firstArray[0], "x")) firstArray[0] = "x";
Conditional array assignment to constant Object.is()
if (!Object.is(firstArray[0], X)) firstArray[0] = X; if (!Object.is(firstArray[1], Y)) firstArray[1] = Y; if (!Object.is(firstArray[2], Z)) firstArray[2] = Z; if (!Object.is(firstArray[3], W)) firstArray[3] = W;
if (!Object.is(firstArray[0], X)) firstArray[0] = X;
if (!Object.is(firstArray[1], Y)) firstArray[1] = Y;
if (!Object.is(firstArray[2], Z)) firstArray[2] = Z;
if (!Object.is(firstArray[3], W)) firstArray[3] = W;
Conditional array reverse assignment to constant Object.is()
if (!Object.is(firstArray[3], W)) firstArray[3] = W; if (!Object.is(firstArray[2], Z)) firstArray[2] = Z; if (!Object.is(firstArray[1], Y)) firstArray[1] = Y; if (!Object.is(firstArray[0], X)) firstArray[0] = X;
if (!Object.is(firstArray[3], W)) firstArray[3] = W;
if (!Object.is(firstArray[2], Z)) firstArray[2] = Z;
if (!Object.is(firstArray[1], Y)) firstArray[1] = Y;
if (!Object.is(firstArray[0], X)) firstArray[0] = X;
Conditional array assignment to variable Object.is()
if (!Object.is(firstArray[0], x)) firstArray[0] = x; if (!Object.is(firstArray[1], y)) firstArray[1] = y; if (!Object.is(firstArray[2], z)) firstArray[2] = z; if (!Object.is(firstArray[3], w)) firstArray[3] = w;
if (!Object.is(firstArray[0], x)) firstArray[0] = x;
if (!Object.is(firstArray[1], y)) firstArray[1] = y;
if (!Object.is(firstArray[2], z)) firstArray[2] = z;
if (!Object.is(firstArray[3], w)) firstArray[3] = w;
Conditional array reverse assignment to variable Object.is()
if (!Object.is(firstArray[3], w)) firstArray[3] = w; if (!Object.is(firstArray[2], z)) firstArray[2] = z; if (!Object.is(firstArray[1], y)) firstArray[1] = y; if (!Object.is(firstArray[0], x)) firstArray[0] = x;
if (!Object.is(firstArray[3], w)) firstArray[3] = w;
if (!Object.is(firstArray[2], z)) firstArray[2] = z;
if (!Object.is(firstArray[1], y)) firstArray[1] = y;
if (!Object.is(firstArray[0], x)) firstArray[0] = x;
Conditional array assignment to array Object.is()
const second0 = secondArray[0]; const second1 = secondArray[1]; const second2 = secondArray[2]; const second3 = secondArray[3]; if (!Object.is(firstArray[0], second0)) firstArray[0] = second0; if (!Object.is(firstArray[1], second1)) firstArray[1] = second1; if (!Object.is(firstArray[2], second2)) firstArray[2] = second2; if (!Object.is(firstArray[3], second3)) firstArray[3] = second3;
const second0 = secondArray[0];
const second1 = secondArray[1];
const second2 = secondArray[2];
const second3 = secondArray[3];
if (!Object.is(firstArray[0], second0)) firstArray[0] = second0;
if (!Object.is(firstArray[1], second1)) firstArray[1] = second1;
if (!Object.is(firstArray[2], second2)) firstArray[2] = second2;
if (!Object.is(firstArray[3], second3)) firstArray[3] = second3;
Conditional array reverse assignment to array Object.is()
const second3 = secondArray[3]; const second2 = secondArray[2]; const second1 = secondArray[1]; const second0 = secondArray[0]; if (!Object.is(firstArray[3], second3)) firstArray[3] = second3; if (!Object.is(firstArray[2], second2)) firstArray[2] = second2; if (!Object.is(firstArray[1], second1)) firstArray[1] = second1; if (!Object.is(firstArray[0], second0)) firstArray[0] = second0;
const second3 = secondArray[3];
const second2 = secondArray[2];
const second1 = secondArray[1];
const second0 = secondArray[0];
if (!Object.is(firstArray[3], second3)) firstArray[3] = second3;
if (!Object.is(firstArray[2], second2)) firstArray[2] = second2;
if (!Object.is(firstArray[1], second1)) firstArray[1] = second1;
if (!Object.is(firstArray[0], second0)) firstArray[0] = second0;
Loop from start with literal length
for (let i = 0; i < 4; i += 1) { firstArray[i] = secondArray[i]; }
for (let i = 0; i < 4; i += 1) {
firstArray[i] = secondArray[i];
}
Loop from end with literal length
for (let i = 4 - 1; i >= 0; i -= 1) { firstArray[i] = secondArray[i]; }
for (let i = 4 - 1; i >= 0; i -= 1) {
firstArray[i] = secondArray[i];
}
Loop from start with constant length
const length = 4; for (let i = 0; i < 4; i += 1) { firstArray[i] = secondArray[i]; }
const length = 4;
for (let i = 0; i < 4; i += 1) {
firstArray[i] = secondArray[i];
}
Loop from end with constant length
const length = 4; for (let i = length - 1; i >= 0; i -= 1) { firstArray[i] = secondArray[i]; }
const length = 4;
for (let i = length - 1; i >= 0; i -= 1) {
firstArray[i] = secondArray[i];
}
Loop from start with constant first length
const length = firstArray.length; for (let i = 0; i < length; i += 1) { firstArray[i] = secondArray[i]; }
const length = firstArray.length;
for (let i = 0; i < length; i += 1) {
firstArray[i] = secondArray[i];
}
Loop from end with constant first length
const length = firstArray.length; for (let i = length - 1; i >= 0; i -= 1) { firstArray[i] = secondArray[i]; }
const length = firstArray.length;
for (let i = length - 1; i >= 0; i -= 1) {
firstArray[i] = secondArray[i];
}
Loop from start with constant second length
const length = secondArray.length; for (let i = 0; i < length; i += 1) { firstArray[i] = secondArray[i]; }
const length = secondArray.length;
for (let i = 0; i < length; i += 1) {
firstArray[i] = secondArray[i];
}
Loop from end with constant second length
const length = secondArray.length; for (let i = length - 1; i >= 0; i -= 1) { firstArray[i] = secondArray[i]; }
const length = secondArray.length;
for (let i = length - 1; i >= 0; i -= 1) {
firstArray[i] = secondArray[i];
}
Loop from start with variable first length
let length = firstArray.length; for (let i = 0; i < length; i += 1) { firstArray[i] = secondArray[i]; }
let length = firstArray.length;
for (let i = 0; i < length; i += 1) {
firstArray[i] = secondArray[i];
}
Loop from end with variable first length
let length = firstArray.length; for (let i = length - 1; i >= 0; i -= 1) { firstArray[i] = secondArray[i]; }
let length = firstArray.length;
for (let i = length - 1; i >= 0; i -= 1) {
firstArray[i] = secondArray[i];
}
Loop from start with variable second length
let length = secondArray.length; for (let i = 0; i < length; i += 1) { firstArray[i] = secondArray[i]; }
let length = secondArray.length;
for (let i = 0; i < length; i += 1) {
firstArray[i] = secondArray[i];
}
Loop from end with variable second length
let length = secondArray.length; for (let i = length - 1; i >= 0; i -= 1) { firstArray[i] = secondArray[i]; }
let length = secondArray.length;
for (let i = length - 1; i >= 0; i -= 1) {
firstArray[i] = secondArray[i];
}
Loop from start re-evaluating first length
for (let i = 0; i < firstArray.length; i += 1) { firstArray[i] = secondArray[i]; }
for (let i = 0; i < firstArray.length; i += 1) {
firstArray[i] = secondArray[i];
}
Loop from end evaluating first length
for (let i = firstArray.length - 1; i >= 0; i -= 1) { firstArray[i] = secondArray[i]; }
for (let i = firstArray.length - 1; i >= 0; i -= 1) {
firstArray[i] = secondArray[i];
}
Loop from start re-evaluating second length
for (let i = 0; i < secondArray.length; i += 1) { firstArray[i] = secondArray[i]; }
for (let i = 0; i < secondArray.length; i += 1) {
firstArray[i] = secondArray[i];
}
Loop from end evaluating second length
for (let i = secondArray.length - 1; i >= 0; i -= 1) { firstArray[i] = secondArray[i]; }
for (let i = secondArray.length - 1; i >= 0; i -= 1) {
firstArray[i] = secondArray[i];
}
Loop in first
for (const i in firstArray) { firstArray[i] = secondArray[i]; }
for (const i in firstArray) {
firstArray[i] = secondArray[i];
}
Loop in second
for (const i in secondArray) { firstArray[i] = secondArray[i]; }
for (const i in secondArray) {
firstArray[i] = secondArray[i];
}
Loop of first
let i = 0; for (const _ of firstArray) { firstArray[i] = secondArray[i]; i += 1; }
let i = 0;
for (const _ of firstArray) {
firstArray[i] = secondArray[i];
i += 1;
}
Loop of second
let i = 0; for (const e of secondArray) { firstArray[i] = e; i += 1; }
let i = 0;
for (const e of secondArray) {
firstArray[i] = e;
i += 1;
}
.forEach() on first
firstArray.forEach(function (_, i, a) { a[i] = this[i]; }, secondArray);
firstArray.forEach(function (_, i, a) {
a[i] = this[i];
}, secondArray);
.forEach() on first closure
firstArray.forEach(function (_, i, a) { a[i] = secondArray[i]; });
firstArray.forEach(function (_, i, a) {
a[i] = secondArray[i];
});
.forEach() on second
secondArray.forEach(function (e, i, _) { this[i] = e; }, firstArray);
secondArray.forEach(function (e, i, _) {
this[i] = e;
}, firstArray);
.forEach() on second closure
secondArray.forEach(function (e, i, _) { firstArray[i] = e; });
secondArray.forEach(function (e, i, _) {
firstArray[i] = e;
});
Array-destructuring constant binding
const [ first0, first1, first2, first3 ] = secondArray;
const [ first0, first1, first2, first3 ] = secondArray;
Array-destructuring variable binding
let [ first0, first1, first2, first3 ] = secondArray;
let [ first0, first1, first2, first3 ] = secondArray;
Array-destructuring variable assignment
[ a, b, c, d ] = secondArray;
[ a, b, c, d ] = secondArray;
Array-destructuring element assignment
([ firstArray[0], firstArray[1], firstArray[2], firstArray[3] ] = secondArray);
([ firstArray[0], firstArray[1], firstArray[2], firstArray[3] ] = secondArray);
Array-destructuring rest assignment
// cannot use firstArray, it's const ([ ...firstArray2 ] = secondArray);
// cannot use firstArray, it's const
([ ...firstArray2 ] = secondArray);
Object-destructuring constant binding with numbers
const { 0: first0, 1: first1, 2: first2, 3: first3 } = secondArray;
const { 0: first0, 1: first1, 2: first2, 3: first3 } = secondArray;
Object-destructuring reverse constant binding with numbers
const { 3: first3, 2: first2, 1: first1, 0: first0 } = secondArray;
const { 3: first3, 2: first2, 1: first1, 0: first0 } = secondArray;
Object-destructuring variable binding with numbers
let { 0: first0, 1: first1, 2: first2, 3: first3 } = secondArray;
let { 0: first0, 1: first1, 2: first2, 3: first3 } = secondArray;
Object-destructuring reverse variable binding with numbers
let { 3: first3, 2: first2, 1: first1, 0: first0 } = secondArray;
let { 3: first3, 2: first2, 1: first1, 0: first0 } = secondArray;
Object-destructuring variable assignment with numbers
({ 0: a, 1: b, 2: c, 3: d } = secondArray);
({ 0: a, 1: b, 2: c, 3: d } = secondArray);
Object-destructuring reverse variable assignment with numbers
({ 3: d, 2: c, 1: b, 0: a } = secondArray);
({ 3: d, 2: c, 1: b, 0: a } = secondArray);
Object-destructuring element assignment with numbers
({ 0: firstArray[0], 1: firstArray[1], 2: firstArray[2], 3: firstArray[3] } = secondArray);
({ 0: firstArray[0], 1: firstArray[1], 2: firstArray[2], 3: firstArray[3] } = secondArray);
Object-destructuring reverse element assignment with numbers
({ 3: firstArray[3], 2: firstArray[2], 1: firstArray[1], 0: firstArray[0] } = secondArray);
({ 3: firstArray[3], 2: firstArray[2], 1: firstArray[1], 0: firstArray[0] } = secondArray);
Object-destructuring constant binding with strings
const { "0": first0, "1": first1, "2": first2, "3": first3 } = secondArray;
const { "0": first0, "1": first1, "2": first2, "3": first3 } = secondArray;
Object-destructuring reverse constant binding with strings
const { "3": first3, "2": first2, "1": first1, "0": first0 } = secondArray;
const { "3": first3, "2": first2, "1": first1, "0": first0 } = secondArray;
Object-destructuring variable binding with strings
let { "0": first0, "1": first1, "2": first2, "3": first3 } = secondArray;
let { "0": first0, "1": first1, "2": first2, "3": first3 } = secondArray;
Object-destructuring reverse variable binding with strings
let { "3": first3, "2": first2, "1": first1, "0": first0 } = secondArray;
let { "3": first3, "2": first2, "1": first1, "0": first0 } = secondArray;
Object-destructuring variable assignment with strings
({ "0": a, "1": b, "2": c, "3": d } = secondArray);
({ "0": a, "1": b, "2": c, "3": d } = secondArray);
Object-destructuring reverse variable assignment with strings
({ "3": d, "2": c, "1": b, "0": a } = secondArray);
({ "3": d, "2": c, "1": b, "0": a } = secondArray);
Object-destructuring element assignment with strings
({ "0": firstArray[0], "1": firstArray[1], "2": firstArray[2], "3": firstArray[3] } = secondArray);
({ "0": firstArray[0], "1": firstArray[1], "2": firstArray[2], "3": firstArray[3] } = secondArray);
Object-destructuring reverse element assignment with strings
({ "3": firstArray[3], "2": firstArray[2], "1": firstArray[1], "0": firstArray[0] } = secondArray);
({ "3": firstArray[3], "2": firstArray[2], "1": firstArray[1], "0": firstArray[0] } = secondArray);
Object-destructuring rest assignment
// cannot use firstArray, it's const ({ ...firstArray2 } = secondArray);
// cannot use firstArray, it's const
({ ...firstArray2 } = secondArray);
Object.assign()
Object.assign(firstArray, secondArray);
Object.assign(firstArray, secondArray);
Do nothing at the end, warm hardware
;
;

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Experimental features:

Memory measurements supported only in Chrome.
For precise memory measurements Chrome must be launched with --enable-precise-memory-info flag.
More information: Monitoring JavaScript Memory

Test case name	Result
Do nothing at the beginning, cold hardware
Constant binding to literal
Constant binding to constant
Constant binding to variable
Constant binding to array
Constant reverse binding to array
Variable binding to literal
Variable binding to constant
Variable binding to variable
Variable binding to array
Variable reverse binding to array
Variable assignment to literal
Variable assignment to constant
Variable assignment to variable
Variable assignment to array
Variable reverse assignment to array
Array assignment to literal
Array reverse assignment to literal
Array assignment to constant
Array reverse assignment to constant
Array assignment to variable
Array reverse assignment to variable
Array assignment to array
Array reverse assignment to array
Conditional variable assignment to literal !==
Conditional variable assignment to constant !==
Conditional variable assignment to variable !==
Conditional variable assignment to array !==
Conditional variable reverse assignment to array !==
Conditional array assignment to literal !==
Conditional array reverse assignment to literal !==
Conditional array assignment to constant !==
Conditional array reverse assignment to constant !==
Conditional array assignment to variable !==
Conditional array reverse assignment to variable !==
Conditional array assignment to array !==
Conditional array reverse assignment to array !==
Conditional variable assignment to literal Object.is()
Conditional variable assignment to constant Object.is()
Conditional variable assignment to variable Object.is()
Conditional variable assignment to array Object.is()
Conditional variable reverse assignment to array Object.is()
Conditional array assignment to literal Object.is()
Conditional array reverse assignment to literal Object.is()
Conditional array assignment to constant Object.is()
Conditional array reverse assignment to constant Object.is()
Conditional array assignment to variable Object.is()
Conditional array reverse assignment to variable Object.is()
Conditional array assignment to array Object.is()
Conditional array reverse assignment to array Object.is()
Loop from start with literal length
Loop from end with literal length
Loop from start with constant length
Loop from end with constant length
Loop from start with constant first length
Loop from end with constant first length
Loop from start with constant second length
Loop from end with constant second length
Loop from start with variable first length
Loop from end with variable first length
Loop from start with variable second length
Loop from end with variable second length
Loop from start re-evaluating first length
Loop from end evaluating first length
Loop from start re-evaluating second length
Loop from end evaluating second length
Loop in first
Loop in second
Loop of first
Loop of second
.forEach() on first
.forEach() on first closure
.forEach() on second
.forEach() on second closure
Array-destructuring constant binding
Array-destructuring variable binding
Array-destructuring variable assignment
Array-destructuring element assignment
Array-destructuring rest assignment
Object-destructuring constant binding with numbers
Object-destructuring reverse constant binding with numbers
Object-destructuring variable binding with numbers
Object-destructuring reverse variable binding with numbers
Object-destructuring variable assignment with numbers
Object-destructuring reverse variable assignment with numbers
Object-destructuring element assignment with numbers
Object-destructuring reverse element assignment with numbers
Object-destructuring constant binding with strings
Object-destructuring reverse constant binding with strings
Object-destructuring variable binding with strings
Object-destructuring reverse variable binding with strings
Object-destructuring variable assignment with strings
Object-destructuring reverse variable assignment with strings
Object-destructuring element assignment with strings
Object-destructuring reverse element assignment with strings
Object-destructuring rest assignment
Object.assign()
Do nothing at the end, warm hardware

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 5 months ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/131.0.0.0 Safari/537.36

Browser/OS: Chrome 131 on Windows

View result in a separate tab

Test name	Executions per second
Do nothing (leave at the beginning, hardware warm up)	57478832.0 Ops/sec
Constant binding to literal	57676348.0 Ops/sec
Constant binding to constant	38365084.0 Ops/sec
Constant binding to variable	44917524.0 Ops/sec
Constant binding to array	38813616.0 Ops/sec
Constant reverse binding to array	37950436.0 Ops/sec
Variable binding to literal	62922236.0 Ops/sec
Variable binding to constant	44701200.0 Ops/sec
Variable binding to variable	44472068.0 Ops/sec
Variable binding to array	38883008.0 Ops/sec
Variable reverse binding to array	37504864.0 Ops/sec
Variable assignment to literal	1200615.4 Ops/sec
Variable assignment to constant	1226941.1 Ops/sec
Variable assignment to variable	1300063.2 Ops/sec
Variable assignment to array	1270750.2 Ops/sec
Variable reverse assignment to array	1244738.9 Ops/sec
Array assignment to literal	29425548.0 Ops/sec
Array reverse assignment to literal	27969364.0 Ops/sec
Array assignment to constant	24637108.0 Ops/sec
Array reverse assignment to constant	23982702.0 Ops/sec
Array assignment to variable	21835088.0 Ops/sec
Array reverse assignment to variable	21984274.0 Ops/sec
Array assignment to array	18808360.0 Ops/sec
Array reverse assignment to array	19444828.0 Ops/sec
Conditional variable assignment to literal !==	33192938.0 Ops/sec
Conditional variable assignment to constant !==	28093182.0 Ops/sec
Conditional variable assignment to variable !==	28372002.0 Ops/sec
Conditional variable assignment to array !==	28110302.0 Ops/sec
Conditional variable reverse assignment to array !==	28025650.0 Ops/sec
Conditional array assignment to literal !==	33255812.0 Ops/sec
Conditional array reverse assignment to literal !==	30802484.0 Ops/sec
Conditional array assignment to constant !==	21015598.0 Ops/sec
Conditional array reverse assignment to constant !==	23299324.0 Ops/sec
Conditional array assignment to variable !==	28490798.0 Ops/sec
Conditional array reverse assignment to variable !==	24140354.0 Ops/sec
Conditional array assignment to array !==	22638614.0 Ops/sec
Conditional array reverse assignment to array !==	21415974.0 Ops/sec
Conditional variable assignment to literal Object.is()	21240844.0 Ops/sec
Conditional variable assignment to constant Object.is()	20533852.0 Ops/sec
Conditional variable assignment to variable Object.is()	21149526.0 Ops/sec
Conditional variable assignment to array Object.is()	20102334.0 Ops/sec
Conditional variable reverse assignment to array Object.is()	18845834.0 Ops/sec
Conditional array assignment to literal Object.is()	22211558.0 Ops/sec
Conditional array reverse assignment to literal Object.is()	21639946.0 Ops/sec
Conditional array assignment to constant Object.is()	21027210.0 Ops/sec
Conditional array reverse assignment to constant Object.is()	21210166.0 Ops/sec
Conditional array assignment to variable Object.is()	21095758.0 Ops/sec
Conditional array reverse assignment to variable Object.is()	21350422.0 Ops/sec
Conditional array assignment to array Object.is()	18899040.0 Ops/sec
Conditional array reverse assignment to array Object.is()	19282466.0 Ops/sec
Loop from start with literal length	19614166.0 Ops/sec
Loop from end with literal length	18465244.0 Ops/sec
Loop from start with constant length	19443376.0 Ops/sec
Loop from end with constant length	19740880.0 Ops/sec
Loop from start with constant first length	16050165.0 Ops/sec
Loop from end with constant first length	17078096.0 Ops/sec
Loop from start with constant second length	15191005.0 Ops/sec
Loop from end with constant second length	15773020.0 Ops/sec
Loop from start with variable first length	15583005.0 Ops/sec
Loop from end with variable first length	16379137.0 Ops/sec
Loop from start with variable second length	15854480.0 Ops/sec
Loop from end with variable second length	15960315.0 Ops/sec
Loop from start re-evaluating first length	14691269.0 Ops/sec
Loop from end evaluating first length	16547016.0 Ops/sec
Loop from start re-evaluating second length	13889201.0 Ops/sec
Loop from end evaluating second length	16971996.0 Ops/sec
Loop in first	1989614.5 Ops/sec
Loop in second	1932137.9 Ops/sec
Loop of first	17988788.0 Ops/sec
Loop of second	21630276.0 Ops/sec
.forEach() on first	6480733.5 Ops/sec
.forEach() on first closure	15407853.0 Ops/sec
.forEach() on second	7516918.5 Ops/sec
.forEach() on second closure	14721358.0 Ops/sec
Array-destructuring constant binding	43363372.0 Ops/sec
Array-destructuring variable binding	42272040.0 Ops/sec
Array-destructuring variable assignment	1078004.5 Ops/sec
Array-destructuring element assignment	17102096.0 Ops/sec
Array-destructuring rest assignment	2698267.0 Ops/sec
Object-destructuring constant binding with numbers	39534520.0 Ops/sec
Object-destructuring reverse constant binding with numbers	44117768.0 Ops/sec
Object-destructuring variable binding with numbers	49794924.0 Ops/sec
Object-destructuring reverse variable binding with numbers	48931360.0 Ops/sec
Object-destructuring variable assignment with numbers	1385889.4 Ops/sec
Object-destructuring reverse variable assignment with numbers	1414131.5 Ops/sec
Object-destructuring element assignment with numbers	22839016.0 Ops/sec
Object-destructuring reverse element assignment with numbers	23307198.0 Ops/sec
Object-destructuring constant binding with strings	49664060.0 Ops/sec
Object-destructuring reverse constant binding with strings	49764324.0 Ops/sec
Object-destructuring variable binding with strings	45665976.0 Ops/sec
Object-destructuring reverse variable binding with strings	49085320.0 Ops/sec
Object-destructuring variable assignment with strings	1387436.0 Ops/sec
Object-destructuring reverse variable assignment with strings	1414204.4 Ops/sec
Object-destructuring element assignment with strings	22813556.0 Ops/sec
Object-destructuring reverse element assignment with strings	22832166.0 Ops/sec
Object-destructuring rest assignment	350344.6 Ops/sec
Do nothing (leave at the end, hardware is warmed up)	57665884.0 Ops/sec

Autogenerated LLM Summary (model gpt-4o-mini, generated 5 months ago):

The provided JSON describes a benchmarking setup for testing various methods of array element assignment in JavaScript, specifically the process of replacing the contents of one array with another. Each method is assessed for its performance, measured in executions per second, with the aim of determining which approach is the most efficient.

Overview of the Benchmark

The benchmark focuses primarily on the following types of operations:

Constant binding: Assigning values based on constants (literals or predefined constants).
Variable binding: Assigning values based on variables.
Array binding: Assignments sourced from the contents of another array.
Conditional assignments: Elements are assigned only if they differ from the existing value, bypassing unnecessary assignments.
Looping techniques: Different methods to loop through arrays from both the beginning and end, and how different array lengths affect performance.
Destructuring assignments: Leveraging ES6 destructuring syntax to assign values from one array to another.

Comparison of Options

Constant vs. Variable Binding:
- Pro: Constant binding (e.g., const first0 = "x";) tends to be faster as it involves no variable lookups— the values are fixed.
- Con: Variable binding (e.g., let first0 = x;) may introduce overhead due to variable lookups, potentially slowing down execution.
Direct Array Assignment vs. Conditional Assignment:
- Pro: Conditional assignments (e.g., if (a !== "x") a = "x";) minimize unnecessary updates, improving performance in cases where values are likely to remain unchanged.
- Con: However, the overhead of condition checks may slow down execution in cases where the values are routinely different.
For-Loops vs. forEach:
- Pro: Traditional for-loops (e.g., for (let i = 0; i < length; i++)) are typically faster due to less overhead compared to higher-level abstractions like forEach, which involves a function call for each iteration.
- Con: forEach provides a more readable syntax which can be advantageous for maintainability.
Destructuring:
- Pro: Destructuring (e.g., const [first0, first1] = secondArray;) allows for a succinct syntax which can improve code clarity.
- Con: However, destructuring has additional overhead compared to manual assignments, especially with Object destructuring for non-integer keys.

Libraries and Features Utilized

Object.assign(): This method is used for object copying, referencing properties and values from one object to another. It's significant for merging values from one structure into another, though it may introduce some overhead compared to direct assignment.
ES6 Features: The benchmark utilizes modern JavaScript features like arrow functions, destructuring, and let/const declarations, which are more performant in many cases than their older counterparts (var).

Alternatives

Map/Set: Using data structures like Map or Set can provide different access and assignment behaviors, particularly in more complex data transformation scenarios.
Libraries: Libraries such as Lodash or Ramda often provide utility functions to manipulate arrays more declaratively, which may suit specific use cases but carry their overhead.
Typed Arrays: For performance-critical applications, using typed arrays or web assembly could yield better performance for numerical data.

Conclusion

This benchmarking suite provides valuable insights into the performance implications of various array assignment techniques in JavaScript. By comparing performance across different approaches, developers can choose the most efficient techniques suited for their applications while considering the trade-offs in readability and maintainability of the code. Efficiently handling array assignments can lead to performance improvements, particularly in applications dealing with large datasets or complex data transformations.

LLMs can make mistakes. Check important info.

### Overview of the Benchmark
The benchmark focuses primarily on the following types of operations:
1. **Constant binding**: Assigning values based on constants (literals or predefined constants).
2. **Variable binding**: Assigning values based on variables.
3. **Array binding**: Assignments sourced from the contents of another array.
4. **Conditional assignments**: Elements are assigned only if they differ from the existing value, bypassing unnecessary assignments.
5. **Looping techniques**: Different methods to loop through arrays from both the beginning and end, and how different array lengths affect performance.
6. **Destructuring assignments**: Leveraging ES6 destructuring syntax to assign values from one array to another.

### Comparison of Options
1. **Constant vs. Variable Binding**:
   - **Pro**: **Constant binding** (e.g., `const first0 = "x";`) tends to be faster as it involves no variable lookups— the values are fixed. 
   - **Con**: **Variable binding** (e.g., `let first0 = x;`) may introduce overhead due to variable lookups, potentially slowing down execution.

2. **Direct Array Assignment vs. Conditional Assignment**:
   - **Pro**: Conditional assignments (e.g., `if (a !== "x") a = "x";`) minimize unnecessary updates, improving performance in cases where values are likely to remain unchanged.
   - **Con**: However, the overhead of condition checks may slow down execution in cases where the values are routinely different.

3. **For-Loops vs. `forEach`**:
   - **Pro**: Traditional for-loops (e.g., `for (let i = 0; i < length; i++)`) are typically faster due to less overhead compared to higher-level abstractions like `forEach`, which involves a function call for each iteration.
   - **Con**: `forEach` provides a more readable syntax which can be advantageous for maintainability.

4. **Destructuring**:
   - **Pro**: Destructuring (e.g., `const [first0, first1] = secondArray;`) allows for a succinct syntax which can improve code clarity.
   - **Con**: However, destructuring has additional overhead compared to manual assignments, especially with Object destructuring for non-integer keys.

### Libraries and Features Utilized
- **Object.assign()**: This method is used for object copying, referencing properties and values from one object to another. It's significant for merging values from one structure into another, though it may introduce some overhead compared to direct assignment.
- **ES6 Features**: The benchmark utilizes modern JavaScript features like **arrow functions**, **destructuring**, and **let/const** declarations, which are more performant in many cases than their older counterparts (`var`).

### Alternatives
1. **Map/Set**: Using data structures like `Map` or `Set` can provide different access and assignment behaviors, particularly in more complex data transformation scenarios. 
2. **Libraries**: Libraries such as Lodash or Ramda often provide utility functions to manipulate arrays more declaratively, which may suit specific use cases but carry their overhead.
3. **Typed Arrays**: For performance-critical applications, using typed arrays or web assembly could yield better performance for numerical data.

### Conclusion
This benchmarking suite provides valuable insights into the performance implications of various array assignment techniques in JavaScript. By comparing performance across different approaches, developers can choose the most efficient techniques suited for their applications while considering the trade-offs in readability and maintainability of the code. Efficiently handling array assignments can lead to performance improvements, particularly in applications dealing with large datasets or complex data transformations.

Related benchmarks: