Strings

Table of contents

1. String declaration
2. Manipulating strings
   1. String concatenation
   2. String as array

Being strings used a lot in bioinformatics, let’s see some more details on how to declare and use them.

String declaration

Long strings can benefit from the multiline declaration using triple quotes:

let  program_description = """
  This program will do things on
  your FASTQ files
"""

As usual, you’ll find special escape sequences like \n for newline, \t for a tab-space, and \\ for the backslash itself. If you need to escape too many characters, you can use the raw string literal where you will use two double-quotes to have one, but you can avoid escape other entities:

var escaped_text = "I like \"quotes\" and many \\ backslashes (like \\n or \\t)"
var same_thing =  r"I like ""quotes"" and many \ backslashes (like \n or \t)"

Manipulating strings

String concatenation

The & operator will concatenate strings. It’s an unusual operator, so I gave him its own paragraph.

var name = "Andrea"
var greeting = "Hello, " & name & "!"
greetings &= "!!"    # the usual shortcut for: greetings = greetings & "!!"

String as array

A string is an array of characters, and you can access each character with its (0-based) index:

var letters = "ABCD"
echo letter[0], letter[3]     # will print 'AD'

# you can loop all the letters:
for letter in letters:
  echo " - ", letter