diff options
Diffstat (limited to 'src/algebra/list.spad.pamphlet')
| -rw-r--r-- | src/algebra/list.spad.pamphlet | 35 |
1 files changed, 17 insertions, 18 deletions
diff --git a/src/algebra/list.spad.pamphlet b/src/algebra/list.spad.pamphlet index aec6167f..3e7c6b28 100644 --- a/src/algebra/list.spad.pamphlet +++ b/src/algebra/list.spad.pamphlet @@ -44,12 +44,11 @@ IndexedList(S:Type, mn:Integer): Exports == Implementation where -- a knowledgeable person wants to update it: -- The following LISP dependencies are divided into two groups -- Those that are required --- CONS, EQ, NIL, NULL, RPLACA, RPLACD +-- CONS, EQ, NIL, RPLACA, RPLACD -- Those that are included for efficiency only -- LIST, NCONC2, LENGTH -- Also REVERSE, since it's called in Polynomial Ring - Qnull ==> NULL$Lisp Qpush ==> PUSH$Lisp Exports ==> ListAggregate S @@ -94,13 +93,13 @@ IndexedList(S:Type, mn:Integer): Exports == Implementation where rest(x, n) == for i in 1..n repeat - if Qnull x then error "index out of range" + if empty? x then error "index out of range" x := %tail x x copy x == y := empty() - for i in 0.. while not Qnull x repeat + for i in 0.. while not empty? x repeat if i = cycleMax and cyclic? x then error "cyclic list" y := %makepair(%head x,y) x := %tail x @@ -126,35 +125,35 @@ IndexedList(S:Type, mn:Integer): Exports == Implementation where if S has SetCategory then x = y == %peq(x,y) => true - while not Qnull x and not Qnull y repeat + while not empty? x and not empty? y repeat %head x ~=$S %head y => return false x := %tail x y := %tail y - Qnull x and Qnull y + empty? x and empty? y latex(x : %): String == s : String := "\left[" - while not Qnull x repeat + while not empty? x repeat s := concat(s, latex(%head x)$S)$String x := %tail x - if not Qnull x then s := concat(s, ", ")$String + if not empty? x then s := concat(s, ", ")$String concat(s, " \right]")$String member?(s,x) == - while not Qnull x repeat + while not empty? x repeat if s = %head x then return true else x := %tail x false -- Lots of code from parts of AGGCAT, repeated here to -- get faster compilation concat!(x:%,y:%) == - Qnull x => - Qnull y => x + empty? x => + empty? y => x Qpush(first y,x) QRPLACD(x,rest y)$Lisp x z:=x - while not Qnull %tail z repeat + while not empty? %tail z repeat z:=%tail z QRPLACD(z,y)$Lisp x @@ -163,13 +162,13 @@ IndexedList(S:Type, mn:Integer): Exports == Implementation where if S has SetCategory then removeDuplicates! l == p := l - while not Qnull p repeat + while not empty? p repeat -- p := setrest!(p, remove!(#1 = %head p, %tail p)) -- far too expensive - builds closures etc. pp:=p f:S:=%head p p:=%tail p - while not Qnull (pr:=%tail pp) repeat + while not empty? (pr:=%tail pp) repeat if (%head pr)@S = f then QRPLACD(pp,%tail pr)$Lisp else pp:=pr l @@ -180,17 +179,17 @@ IndexedList(S:Type, mn:Integer): Exports == Implementation where sort!(f, l) == mergeSort(f, l, #l) merge!(f, p, q) == - Qnull p => q - Qnull q => p + empty? p => q + empty? q => p %peq(p, q) => error "cannot merge a list into itself" if f(%head p, %head q) then (r := t := p; p := %tail p) else (r := t := q; q := %tail q) - while not Qnull p and not Qnull q repeat + while not empty? p and not empty? q repeat if f(%head p, %head q) then (QRPLACD(t, p)$Lisp; t := p; p := %tail p) else (QRPLACD(t, q)$Lisp; t := q; q := %tail q) - QRPLACD(t, if Qnull p then q else p)$Lisp + QRPLACD(t, if empty? p then q else p)$Lisp r split!(p, n) == |