let i = 0;
let j = 0
for(let x = 0; x < 100000; x++) {
j++;
}
i = 0;
for(let x = 0; x < 100000; x++) {
i++;
}
--enable-precise-memory-info
flag.
Test case name | Result |
---|---|
with let | |
without let |
Test name | Executions per second |
---|---|
with let | 15576.4 Ops/sec |
without let | 5601.9 Ops/sec |
I'll break down the provided benchmarking data in an easy-to-understand manner.
Benchmark Definition and Options
The benchmark is comparing two JavaScript options:
let
(the option being tested)let
(the baseline option)In other words, the test is measuring how the presence of a variable declaration (let
) affects the performance of the code.
Pros and Cons of each approach:
With let
:
let
variables are scoped to their block, which can improve code organization and readability.let
, variable names might conflict with other global variables, leading to unexpected behavior.let
) might introduce additional overhead due to the creation of a new block.Without let
:
let
might lead to conflicts with other global variables.Library and Special Features
There are no libraries or special features mentioned in the provided benchmarking data. The test cases rely solely on JavaScript's basic syntax.
Other Considerations
for
loop. This block scoping behavior can affect the performance of the code.++
) to increment variables. However, without let
, the variable declaration is implicit and might be subject to some overhead.Alternatives
If you need a better understanding of this benchmark or want to explore different options:
perf_hooks
(Node.js) or Web API's PerformanceObserver
.Keep this information in mind when analyzing the results of this particular benchmark.