const obj = {}
new Array(1000).map((item, index) => {
obj[index] = index
})
const obj = {}
new Array(1000).map((item, index) => {
obj[index] = index
})
return !!Object.keys(obj).length
const obj = {}
new Array(1000).map((item, index) => {
obj[index] = index
})
for(let key in obj){
return true;
}
return false
--enable-precise-memory-info
flag.
Test case name | Result |
---|---|
Object.keys | |
for key .. in |
Test name | Executions per second |
---|---|
Object.keys | 304039.4 Ops/sec |
for key .. in | 338084.7 Ops/sec |
Let's break down the provided JSON data and explain what is being tested.
Benchmark Definition
The benchmark definition represents two different approaches to check if an object has any keys:
Object.keys(obj).length
: This approach uses the built-in Object.keys()
method to get an array of the object's own enumerable property names, and then checks if the length of that array is greater than 0.for (let key in obj) { return true; } return false
: This approach uses a traditional for...in
loop to iterate over the object's properties and checks if any of them are returned.Options Compared
The two options being compared are:
Object.keys()
methodfor...in
loopPros and Cons of Each Approach
1. Using Object.keys()
Pros:
Cons:
2. Using a for...in
loop
Pros:
Cons:
Object.keys()
Library Usage
Neither of the provided benchmarks uses a library. However, it's worth noting that some browsers may use internal libraries or optimizations that could affect the results.
Special JS Feature/Syntax
There is no special JavaScript feature or syntax being used in these benchmarks. Both approaches are standard JavaScript and do not rely on any advanced features like async/await, callbacks, or closures.
Other Alternatives
If you wanted to add more variations to this benchmark, some other options could be:
for...in
with a try-catch
block to handle errorsObject.getOwnPropertyNames()
instead of Object.keys()
Keep in mind that the results may vary depending on the specific browser and environment being tested.