Benchmark: + vs concat - MeasureThat.net

Tests:

+
var test = 'test' + 1
concat
var test = 'test'.concat(1)

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
+
concat

Fastest: N/A

Slowest: N/A

Latest run results:

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Autogenerated LLM Summary (model llama3.2:3b, generated one year ago):

LLMs can make mistakes. Check important info.

Measuring the performance of different approaches to retrieve a specific DOM element is an interesting task.

The provided JSON represents a benchmark test that compares two ways of achieving this goal: using the "+" operator and using the `concat()` method.

**What's being tested?**

In JavaScript, when you want to concatenate a string with a number, like in the `Benchmark Definition` "var test = 'test' + 1", the interpreter has to perform a type coercion. In other words, it needs to convert the number into a string and then concatenate them.

Here are the two options being compared:

**Option 1: Using the "+" operator**

In this approach, you simply add the two values together using the "+" operator. The JavaScript engine will automatically convert the number into a string and perform the concatenation.

Example in code:
```javascript
var test = 'test' + 1;
```
Pros:

* Simple to write and understand
* No need for explicit type conversion

Cons:

* Can be slower due to type coercion
* May not work as expected if the types are different (e.g., concatenating a string with an object)

**Option 2: Using the `concat()` method**

In this approach, you use the `concat()` method to concatenate two strings. However, since JavaScript's `concat()` method takes multiple arguments and returns a new string, it doesn't actually take a number as an argument.

Example in code:
```javascript
var test = 'test'.concat(1);
```
Pros:

* May be faster due to optimized implementation
* Explicitly separates the concatenation operation from the variable declaration

Cons:

* Requires more code and may be less readable
* Can lead to unexpected behavior if not used carefully (e.g., `concat()` can return a different value than expected)

**Other considerations**

* The order of operations: In both cases, the JavaScript engine will perform type coercion before concatenation. However, in some cases, this might affect performance.
* Function invocation vs. expression evaluation: Both options require function invocation or expression evaluation, which can impact performance and readability.

**Library usage**

There is no explicit library mentioned in the provided code snippets. However, keep in mind that using external libraries can significantly impact benchmark results due to factors like dependency overhead, cache misses, or differences in implementation between libraries.

**Special JS features or syntax**

This benchmark does not use any special JavaScript features or syntax beyond what's standard in modern JavaScript implementations.

**Alternatives**

Some alternative approaches for achieving concatenation include:

* Using the `+=` operator (which is equivalent to adding and assigning)
```javascript
var test = 'test';
test += 1;
```
* Using template literals (introduced in ES6+)
```javascript
var test = 'test' + 1; // or `test = "test" + 1;`
```
These alternatives may affect performance, readability, and maintainability, depending on the context and specific use case.

Related benchmarks:

+ vs concat (version: 0)

Test performance of different ways of get just one particular DOM element

Comparing performance of: + vs concat

Created: 6 years ago by: Registered User

Jump to the latest result

+

concat

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

No previous run results

Autogenerated LLM Summary (model llama3.2:3b, generated one year ago):