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Imperative Languages

Essential Features:

• Sequential execution,
• Implicit data structure (the "store")
  • Existence indpendent of any program,
  • Not mentioned in language syntax,
  • Phrases may access it and update it.

Relationship between store and programs:

1. Critical for evaluation of phrases.

   Phrase meaning depends on store.

2. Communication between phrases.

   Phrases deposit values in store for use by other phrases; sequencing mechanism establishes communication order.

3. Inherently "large" argument.

   Only one copy existing during execution.