ABC has only five data types that can easily be combined; strong typing, yet without declarations; data limited only by memory; refinements to support top-down programming; nesting by indentation. Programs are typically around a quarter the size of the equivalent Pascal or C program, and more readable.
ABC includes a programming environment with syntax-directed editing, suggestions, persistent variables and multiple workspaces and infinite precision arithmetic.
An example function words to collect the set of all words in a document:
HOW TO RETURN words document: PUT {} IN collection FOR line in document: FOR word IN split line: IF word not.in collection: INSERT word IN collection RETURN collectionInterpreter/compiler, version 1.05.02, by Leo Geurts, Lambert Meertens, Steven Pemberton
ABC was one of the influences in the design of the Python programming language.
See also Programming
External links
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