A quantitative model for simply typed λ-calculus

We use a simplified version of the framework of resource monoids, introduced by Dal Lago and Hofmann (2005, 2011), to interpret simply typed λ -calculus with constants zero and successor. We then use this model to prove a simple quantitative result about bounding the size of the normal form of λ -terms. While the bound itself is already known, this is to our knowledge the first semantic proof of this fact. Our use of resource monoids differs from the other instances found in the literature, in that it measures the size of λ -terms rather than time complexity

Deriving Type Checkers

The relationship between a type system’s specification and the implementation of the type checker is a recurring issue when writing compilers for programming languages and it is an ongoing question if – and if so, how – the formal description of a type system can be used to support the compiler writer when implementing the type checking phase. In this paper we propose type systems formalized by constraintbased inference rules to form an ideal abstraction to accomplish the task of automatically deriving type checking functionality from them. We develop a set of algorithms employing the constraint-based flavor of the rules to perform type checks and present the design and implementation of a Haskell library utilizing these algorithms to provide functionality for the type checking phase based on the chosen abstraction

Code mobility and Java RMI

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