sexp
Interface SList

All Superinterfaces:

Iterable<SExp>, SExp

All Known Implementing Classes:

SEmpty, SNonEmpty

public interface SList
extends SExp, Iterable<SExp>

SList represents an expression consisting of a list of subexpressions, e.g. (a b c). The methods of SList offer three patterns for iterating over the subexpressions:

• By removing the first element: use first(), rest(), and isEmpty().
• By indexing down the list: use get() and size().
• By Iterator: use iterator() or the for(var:list) {...} syntax.

isEmpty

boolean isEmpty()

Returns:

first

SExp first()

Returns:

first expression in this list

Requires:

this list is not empty

rest

SList rest()

Returns:

remaining expressions after removing the first

Requires:

this list is not empty

size

int size()

Returns:

number of subexpressions, i.e. elements in this list

get

SExp get(int i)

Returns:

ith element of this list, numbered from 0

Requires:

0 <= i < size()

iterator

Iterator<SExp> iterator()

Specified by:

iterator in interface Iterable<SExp>

Returns:

iterator that yields the subexpressions of this list in order from left to right