8.1. GLOSSARY¶
- alpha¶
The name of the Greek letter \(\alpha\) (lowercase) or \(A\) (uppercase), corresponding to the letter “a”.
- binding occurrence¶
A binding occurrence is the place in a program where a variable is bound to its name (or identifier). In modern programming languages, a binding occurrence is the same as a declaration of the variable. In lambda calculus, a binding occurrence for, say, the variable \(x\), is any sub-expression equal to \(\lambda x.\)
- bnf grammar¶
A BNF grammar is…
- bound¶
In a lambda expression, a variable occurrence is bound or occurs bound if it belongs to the scope of a binding occurrence of that variable.
- free¶
In a lambda expression, a variable occurrence is free or occurs free if it is not bound in that expression.
- function abstraction¶
In lambda calculus, a function abstraction (or lambda abstraction) is synonymous with a function definition that contains the name of the formal parameter and the body of the function.
- lambda¶
The name of the Greek letter \(\lambda\) (lowercase) or \(\Lambda\) (uppercase), corresponding to the letter “L”.
- lambda abstraction¶
Synonym for function abstraction.
- scope¶
Abbreviation for variable scope
- variable capture¶
A free variable occurrence is captured when it becomes bound following the renaming of some other variable occurrence.
- variable scope¶
The scope of a variable declaration (or binding occurrence) in a program is the collection of all parts of the program (that is, the lines of code) in which this variable is accessible via its name or identifier.