Node:SRFI-1 Predicates,
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39.3.2 Predicates
The procedures in this section test specific properties of lists.
| proper-list? obj
|
Scheme Procedure |
Return #t if obj is a proper list, that is a finite list,
terminated with the empty list. Otherwise, return #f.
|
| circular-list? obj
|
Scheme Procedure |
Return #t if obj is a circular list, otherwise return
#f.
|
| dotted-list? obj
|
Scheme Procedure |
Return #t if obj is a dotted list, return #f
otherwise. A dotted list is a finite list which is not terminated by
the empty list, but some other value.
|
| null-list? lst
|
Scheme Procedure |
Return #t if lst is the empty list (), #f
otherwise. If something else than a proper or circular list is passed
as lst, an error is signalled. This procedure is recommended
for checking for the end of a list in contexts where dotted lists are
not allowed.
|
| not-pair? obj
|
Scheme Procedure |
Return #t is obj is not a pair, #f otherwise.
This is shorthand notation (not (pair? obj)) and is
supposed to be used for end-of-list checking in contexts where dotted
lists are allowed.
|
| list= elt= list1 ...
|
Scheme Procedure |
Return #t if all argument lists are equal, #f otherwise.
List equality is determined by testing whether all lists have the same
length and the corresponding elements are equal in the sense of the
equality predicate elt=. If no or only one list is given,
#t is returned.
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