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@@ -0,0 +1,34 @@
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+Associative arrays are indexed by string keys. The basic operations on a such array is storing a value (having declared type) and extracting the value given the key (string).
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+
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+### Syntax
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+Associative arrays are declared using keyword *MAP*:
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+
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+ VAR m: MAP OF INTEGER; (* m is associative array storing integer values *)
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+
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+ TYPE T = RECORD field: MAP OF T END; (* associative array can have records as values *)
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+
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+### Semantics
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+Notation similar to ordinary arrays is used to acceess, add a new element or replace existing element (with the same key) in associative array:
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+
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+ m[key] := value; (* add/replace element *)
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+ value := m[key]; (* get element *)
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+
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+_key_ type should be compatible with [[STRING|eberon-strings]] and _value_ should be compatible with declared type. Attempt to access element with non-existing key will break program execution.
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+
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+Keyword *IN* is used to test whether element with specified key is present in the array:
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+
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+ IF key IN m THEN
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+
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+It is also possible to iterate through associative array keys/values using *FOR..IN* loop:
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+
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+ FOR key, value IN m DO END
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+
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+Here _key_ and _value_ are variables assigned to each key/value pair while iterating through array. These variables have no a separate declaration and their visibility scope is inside loop only. Also these variables are read-only - similar to non-VAR parameters.
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+
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+To remove element from array *remove* method is used:
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+
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+ m.remove(key)
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+
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+To remove all elements from array *clear* method is used:
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+
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+ m.clear()
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Vladislav Folts