Editing Icon (programming language) (section)

===Strings===
In Icon, strings are lists of characters. As a list, they are generators and can thus be iterated over using the bang syntax:

<syntaxhighlight lang="icon">
 write(!"Hello, world!")
</syntaxhighlight>

Will print out each character of the string on a separate line.

Substrings can be extracted from a string by using a range specification within brackets. A range specification can return a point to a single character, or a [[array slicing|slice]] of the string. Strings can be indexed from either the right or the left. Positions within a string are defined to be '''between''' the characters <sub>1</sub>A<sub>2</sub>B<sub>3</sub>C<sub>4</sub> and can be specified from the right <sub>−3</sub>A<sub>−2</sub>B<sub>−1</sub>C<sub>0</sub>

For example,
<syntaxhighlight lang="icon">
 "Wikipedia"[1]     ==> "W"
 "Wikipedia"[3]     ==> "k"
 "Wikipedia"[0]     ==> "a"
 "Wikipedia"[1:3]   ==> "Wi"
 "Wikipedia"[-2:0]  ==> "ia"
 "Wikipedia"[2+:3]  ==> "iki"
</syntaxhighlight>
Where the last example shows using a length instead of an ending position

The subscripting specification can be used as a [[value (computer science)#lrvalue|lvalue]] within an expression. This can be used to insert strings into another string or delete parts of a string. For example:

<syntaxhighlight lang="icon">
    s := "abc"
    s[2] := "123"
    s now has a value of "a123c"
    s := "abcdefg"
    s[3:5] := "ABCD"
    s now has a value of "abABCDefg"
    s := "abcdefg"
    s[3:5] := ""
    s now has a value of "abefg"
</syntaxhighlight>