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deft adds default values for record fields and typecase support to Janet's gradual type system
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Engineers using Janet can now annotate record fields with default values and employ typecase for safer branching while retaining gradual typing benefits.
The gradual type system lets developers add types incrementally while preserving Janet's dynamic feel, aided by bidirectional inference that reduces annotation burden. Static analysis catches type mismatches early, and runtime type checking guards against violations at module boundaries. Recent additions such as default values for record fields and typecase simplify common patterns and reduce boilerplate in Janet programs.
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deft provides bidirectional type inference, static analysis, and optional runtime type checking for Janet.
Recent commits added default values for record fields and typecase (implicit & strict) support.
Other updates improved record guards, inlined define for better performance, and fixed argument handling and shadowing issues.
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deft introduces a gradual type system for Janet that combines bidirectional inference, static analysis, and runtime type checking. The system allows developers to annotate parts of their code while leaving other parts dynamically typed. Recent commits extended the system with default values for record fields and typecase support (implicit & strict). Additional changes improved record guards, added an inlining optimization for define, and fixed optional, keyword and variadic argument handling plus shadowing.
Adopting deft requires engineers to write type annotations to enable the bidirectional inference and static analysis features. Without annotations, the code remains dynamically typed and the static analyzer cannot report type errors. Engineers must keep annotations consistent across functions and records to avoid mismatches that the static analyzer would flag. Runtime type checking is performed to catch mismatches that static analysis may miss.
Static analysis only evaluates code that carries type annotations; unannotated Janet code is treated as dynamically typed. Consequently, missing or incorrect annotations may let type errors slip through to runtime. Runtime checks apply at boundaries between typed and untyped code. Thus, the safety guarantees of deft depend on the extent of annotation coverage and the discipline of maintaining correct types.
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