Let's dive into the world of performance benchmarking with MeasureThat.net.

Benchmark Definition

The provided JSON represents a benchmark that compares the performance of two approaches: Lodash's _.pickBy() function and native JavaScript's Object.entries().filter() method. The benchmark is designed to measure the speed of each approach in extracting specific properties from an object based on a predicate function.

Options Compared

Two options are compared:

1. Lodash's _pickBy() function: This function takes two arguments, object and predicate, where object is the source object, and predicate is a function that returns true for the desired properties. The function iterates through the properties of the object using a for...in loop and includes only the properties for which the predicate function returns true.
2. Native JavaScript's Object.entries().filter() method: This approach uses the entries() method to iterate over an object's key-value pairs, converting it into an array of arrays. The filter() method is then applied to this array, allowing you to specify a callback function that filters out unwanted properties.

Pros and Cons

Here are some pros and cons for each approach:

• Lodash's _pickBy() function:
  • Pros: Easy to use, concise syntax, fast performance due to optimized internal implementation.
  • Cons: Requires an additional library (Lodash) to be included in the benchmark script, can be slower than native JavaScript implementations if not used efficiently.
• Native JavaScript's Object.entries().filter() method:
  • Pros: Fast performance, does not require an additional library, and is a standard part of modern JavaScript engines.
  • Cons: Can be slower for very large objects due to the overhead of creating arrays from object entries, may have higher memory usage.

Library and Syntax Considerations

In this benchmark, Lodash's _.pickBy() function is used. The _pickBy method is a utility function in Lodash that extracts specific properties from an object based on a predicate function. This library provides additional utility functions for array and object manipulation, among others.

There are no special JavaScript features or syntax used in this benchmark. It relies solely on standard JavaScript language features.

Alternatives

For native JavaScript implementations, you can also use other approaches like:

• Using Object.keys() to get an array of keys, then using Array.prototype.filter() to filter out unwanted properties.
• Using Object.getOwnPropertyNames() or Object.getOwnPropertySymbols() (depending on the object type) to iterate over object properties directly.

Keep in mind that each approach has its own performance characteristics and trade-offs. MeasureThat.net helps you compare these different methods under controlled conditions, allowing for a more accurate assessment of their relative performance.