application/octet-stream
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4.04 KB
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155 lines
; Put all the LISt Processing stuff in here
[defun except-last-pair/iter [list rest]
"Iterator for except-last-pair"
[if [nil? [cdr list]]
[reverse rest]
[except-last-pair/iter [cdr list] [cons [car list] rest]]]
]
[defun except-last-pair [list]
"Return a copy of LIST without the last pair"
[except-last-pair/iter list #nil]
]
[defun last-pair [l]
"Return the last pair of l"
[while [cdr l] [cdr! l]]
l
]
[defun make-list [number value]
"Return a list of NUMBER elements containing VALUE in every car"
[def l #nil]
[while [>= [-- number] 0]
[set! l [cons value l]]
]
l
]
[defun list/reduce [o l s]
"Combine all elements in l using operation o and starting value s"
[while l
[set! s [o s [car l]]]
[cdr! l]
]
s
]
[defun list/ref [l i]
"Returns the the element of list l at location i"
[while [and l [> i 0]]
[-- i]
[cdr! l]
]
[car l]
]
[defun reverse [l r]
"Return the list l in reverse order"
[if [nil? l]
r
[reverse [cdr l] [cons [car l] r]]]
]
[defun list/length [l]
"Returns the length of list l"
[def ret 0]
[while l [cdr! l] [++ ret]]
ret
]
[defun list/filter [p l]
"Runs predicate p over every item in list l and returns a list consiting solely of items where p is true"
[def ret #nil]
[if l
[if [p [car l]]
[cons [car l] [filter p [cdr l]]]
[filter p [cdr l]]
#nil]]
]
[defun list/map [f l]
"Runs f over every item in list l and returns the resulting list"
[if [nil? l]
l
[cons [f [car l]] [map f [cdr l]]]]
]
[defun append/iter [a b]
"Iterator for append"
[if [nil? a]
b
[append/iter [cdr a] [cons [car a] b]]]
]
[defun append [a b]
"Appends to two lists a and b together"
[append/iter [reverse a] b]
]
[defun sublist [l start end ret]
"Returns a new list containing all elements of l from start to end"
[cond [[nil? l] [reverse ret]]
[[neg? end] [sublist l start [+ [length l] end]]]
[[zero? end] [reverse ret]]
[[> start 0] [sublist [cdr l] [+ -1 start] [+ -1 end] #nil]]
[[> end 0] [sublist [cdr l] 0 [+ -1 end] [cons [car l] ret]]]
]
]
[defun list-head [l k]
"Returns the first k elemnts of list l"
[sublist l 0 k]
]
[defun list-tail [l k]
"Returns the sublist of l obtained by omitting the first l elements"
[sublist l k [length l]]
]
[defun member [m l]
"Returns the first pair of list l whose car is equal to m"
[cond [[nil? l] #f]
[[== [car l] m] l]
[#t [member m [cdr l]]]
]
]
[defun delete [e l]
"Returns a filtered list l with all elements equal to e omitted"
[filter [\ [a] [not [== a e]]] l]
]
[defun arg-list [f]
"Return the Argument list of f which can be a Native Function or a Lambda"
[cond [[lambda? f] [reduce cat [map [\ [a] [" " [car a]]] [cl-data f]]]]
[[native? f] [reduce cat [map [\ [a] [" " a]] [car [cl-data f]]]]]
[#t ""]
]
]
[defun getf [l key]
"Return the value in LIST following KEY"
[cond [[nil? l] #nil]
[[== key [car l]] [cadr l]]
[#t [getf [cdr l] key]]
]
]
[defun list/sort [l]
"Terribly slow way to sort a list, though it was simple to write"
[if l
[do [def top [car l]]
[def next #nil]
[cdr! l]
[while l
[if [> [car l] top]
[do [set! next [cons top next]]
[set! top [car l]]]
[set! next [cons [car l] next]]]
[cdr! l]
]
[cons top [list/sort next]]]
#nil]
]
