Node:Strings, Next:Regular Expressions, Previous:Characters, Up:Simple Data Types

21.4 Strings

Strings are fixed-length sequences of characters. They can be created by calling constructor procedures, but they can also literally get entered at the REPL or in Scheme source files.

Guile provides a rich set of string processing procedures, because text handling is very important when Guile is used as a scripting language.

Strings always carry the information about how many characters they are composed of with them, so there is no special end-of-string character, like in C. That means that Scheme strings can contain any character, even the NUL character '\0'. But note: Since most operating system calls dealing with strings (such as for file operations) expect strings to be zero-terminated, they might do unexpected things when called with string containing unusual characters.

• String Syntax: Read syntax for strings.
• String Predicates: Testing strings for certain properties.
• String Constructors: Creating new string objects.
• List/String Conversion: Converting from/to lists of characters.
• String Selection: Select portions from strings.
• String Modification: Modify parts or whole strings.
• String Comparison: Lexicographic ordering predicates.
• String Searching: Searching in strings.
• Alphabetic Case Mapping: Convert the alphabetic case of strings.
• Appending Strings: Appending strings to form a new string.