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chrisdone /
Last active Aug 21, 2020
Statically Typed Lisp

Basic unit type:

λ> replTy "()"
() :: ()

Basic functions:

pchiusano / type-inhabitants.markdown
Last active Jan 21, 2020
Reasoning about type inhabitants in Haskell
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This is material to go along with a 2014 Boston Haskell talk.

We are going to look at a series of type signatures in Haskell and explore how parametricity (or lack thereof) lets us constrain what a function is allowed to do.

Let's start with a decidedly non-generic function signature. What are the possible implementations of this function which typecheck?

wrangle :: Int -> Int
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chaitanyagupta /
Last active Oct 19, 2020
Reader Macros in Common Lisp

Reader Macros in Common Lisp

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Reader macros are perhaps not as famous as ordinary macros. While macros are a great way to create your own DSL, reader macros provide even greater flexibility by allowing you to create entirely new syntax on top of Lisp.

Paul Graham explains them very well in [On Lisp][] (Chapter 17, Read-Macros):

The three big moments in a Lisp expression's life are read-time, compile-time, and runtime. Functions are in control at runtime. Macros give us a chance to perform transformations on programs at compile-time. do their work at read-time.

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