No abstract

Visual programming is widely adopted in learning, usually with jigsaw-style blocks that may be freely placed on a canvas. While grammatical correctness is forced by the allowed compositions, syntactic information is not communicated to learners, causing the underlying language grammar to be experientially assimilated. But grammars are crucial for the deeper understanding of languages, since syntax reflects all important semantic aspects and elements. We present a generalpurpose syntax-directed visual editor with syntactic tooltips, accepting as input the grammar of the subject language. It adopts a block-based visual style for program elements. However, contrasting to the typical canvas layout, it supports a row-based grid for spatial organization, enabling newlines and indentation. It also allows users view the production chain of any program element for a better understanding of the language. Our early evaluation findings indicate that such a combination of interactive syntax and visual code blocks is very positively received by learners.