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(guile.info)Association Lists

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Association Lists
-----------------

An association list is a conventional data structure that is often used
to implement simple key-value databases.  It consists of a list of
entries in which each entry is a pair.  The "key" of each entry is the
`car' of the pair and the "value" of each entry is the `cdr'.

     ASSOCIATION LIST ::=  '( (KEY1 . VALUE1)
                              (KEY2 . VALUE2)
                              (KEY3 . VALUE3)
                              ...
                            )

Association lists are also known, for short, as "alists".

The structure of an association list is just one example of the infinite
number of possible structures that can be built using pairs and lists.
As such, the keys and values in an association list can be manipulated
using the general list structure procedures `cons', `car', `cdr',
`set-car!', `set-cdr!' and so on.  However, because association lists
are so useful, Guile also provides specific procedures for manipulating
them.

Alist Key Equality

Adding or Setting Alist Entries

Retrieving Alist Entries

Removing Alist Entries

Sloppy Alist Functions

Alist Example