Programming plans, imagery, and visual programming

Spreadsheets and visual programming languages raise a challenge for existing schema-based models of programming knowledge, which have been scarcely been applied outside Pascal-like languages. Recent demonstrations of the role of mental imagery in spreadsheet programming raise another challenge to schema-based theories, which are propositional in form. We show that a recent schema-based model can be applied to visual languages and report comparisons between elicited mental structures for visual, spreadsheet and textual languages. Although visualness affected elicited structure (which is not predicted by schema theory), results suggest modification of schema theory rather than refutation. Programming environments should support 2D layout better.