Typing environment
In type theory a typing environment (or typing context) represents the association between variable names and data types. More formally an environment  is a set or ordered list of pairs , usually written as , where  is a variable and  its type. The judgement
 
is read as " has type  in context  ". For each function body type checks:

Typing Rules Example:

In statically typed programming languages these environments are used and maintained by typing rules to type check a given program or expression. See also
 Type system

References

Data types
Program analysis
Type theory