Minimal Perl

Chapter 4. Perl as a (better) sed command

4.1	A brief history of sed	89
4.2	Shortcomings of sed	91
4.3	Performing substitutions	93
4.4	Printing lines by number	100
4.5	Modifying templates	101
4.6	Converting special characters	103
4.7	Editing files	105
4.8	Converting to lowercase or uppercase	113
4.9	Substitutions with computed replacements	114
4.10	The sed to Perl translator	118
4.11	Summary	118

In this chapter, you’ll learn how to write Perl programs that surpass the limitations of the UNIX sed command. We’ll start by discussing the historical uses of sed, and then we’ll consider its modern-day applications—which are quite different.^[1]

Then, we’ll explore a variety of commands and scripts that show how Perl can beat sed at its own game.

A brief history of sed

Although it isn’t ...