Learning Functional Programming in Go

Grep sort example

The /etc/group file is the data source. Grep is the first filter whose input is all the lines from the /etc/group file. The grep command removes all lines that do not begin with "com", and then sends its output to the Unix pipe, which sends that data to the sort command:

$ grep "^com" /etc/group | sort
com.apple.access_disabled:*:396:
com.apple.access_ftp:*:395:
com.apple.access_screensharing:*:398:
com.apple.access_sessionkey:*:397:
com.apple.access_ssh:*:399:

Let's be clear. What we're covering in this chapter behaves like Unix pipes, but what we'll study are pipelines that are implemented in Go, mainly using Go channels and Goroutines. Similarly, we will not discuss Go Pipes (https://golang.org/pkg/os/#Pipe) other than ...