Dominoes and storyboards beyond 'icons on strings'

Practically since graphic displays were first hooked to computers, the idea of representing computer programs by pictures has attracted researchers. Most proposals for visual programming languages have adhered to a set pattern: fixed pictures symbolizing program components, connected by lines or arrows symbolizing relationships between the program components. The author explores one alternative: representing a program through visual examples of the state of its execution. He presents to related techniques: dominoes, which replace the traditional icons as representations of operations; and storyboards, which replace iconic circuitry as the representation of program code. These have been implemented in Mondrian, a graphic editor extensible through programming by example.<
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