lof

lof: lower-order function wrappers

Wrap Go builtins for use with higher-order functions. When len or fmt.Println don't match the signature a HOF expects, lof provides compatible wrappers.

A lower-order function is the flip side of a higher-order function—the function being passed, not the one receiving it.

Go builtins like len are operators, not functions—you can't pass len to ToInt. lof wraps them as passable functions.

names.Each(lof.Println)  // print each name

See pkg.go.dev for complete API documentation.

Quick Start

import (
    "github.com/binaryphile/fluentfp/lof"
    "github.com/binaryphile/fluentfp/slice"
)

names := slice.From(users).ToString(User.Name)
names.Each(lof.Println)  // print each name

// When type has no Len() method, lof.Len bridges the gap
type Report struct { Pages []Page }

// pageCount returns the number of pages in a report.
pageCount := func(r Report) int { return lof.Len(r.Pages) }
pageCounts := slice.From(reports).ToInt(pageCount)

API Reference

When NOT to Use lof

• Method expressions exist — User.Name beats wrapping a getter
• Direct calls work — If you're not in a HOF chain, just call len() or fmt.Println()

See Also

For the HOF methods that consume these wrappers, see slice.