Environment (type theory)

In type theory a typing environment (or variable assignment) represents the association between variables names and data types. More formally an environment ${\displaystyle \Gamma }$ is a set or ordered list of pairs ${\displaystyle \langle x,\tau \rangle }$, usually written as ${\displaystyle x:\tau }$, where ${\displaystyle x}$ is a variable and ${\displaystyle \tau }$ its type.

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