-- Copyright (C) 2011, Gabriel Dos Reis. -- All rights reserved. -- -- Redistribution and use in source and binary forms, with or without -- modification, are permitted provided that the following conditions are -- met: -- -- - Redistributions of source code must retain the above copyright -- notice, this list of conditions and the following disclaimer. -- -- - Redistributions in binary form must reproduce the above copyright -- notice, this list of conditions and the following disclaimer in -- the documentation and/or other materials provided with the -- distribution. -- -- - Neither the name of The Numerical Algorithms Group Ltd. nor the -- names of its contributors may be used to endorse or promote products -- derived from this software without specific prior written permission. -- -- THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS -- IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED -- TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A -- PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER -- OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, -- EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, -- PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR -- PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF -- LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING -- NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS -- SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. -- --% --% Definitions in this file provide runtime support for the Boot --% language. As such, some of the definitions (e.g. reverse, append, etc) --% use `unusual' style. These functions are used in code generated --% by the Boot translator. Others are handy library functions. --% namespace BOOTTRAN == import namespace System import namespace AxiomCore namespace BOOTTRAN module utility (objectMember?, symbolMember?, stringMember?, charMember?, scalarMember?, listMember?, reverse, reverse!, lastNode, append, append!, copyList, substitute, substitute!, setDifference, setUnion, setIntersection, applySubst, applySubst!, applySubstNQ, objectAssoc, remove,removeSymbol,atomic?,finishLine) where substitute: (%Thing,%Thing,%Thing) -> %Thing substitute!: (%Thing,%Thing,%Thing) -> %Thing append: (%List %Thing,%List %Thing) -> %List %Thing append!: (%List %Thing,%List %Thing) -> %List %Thing copyList: %List %Thing -> %List %Thing lastNode: %List %Thing -> %Maybe %Node %Thing removeSymbol: (%List %Thing, %Symbol) -> %List %Thing remove: (%List %Thing, %Thing) -> %List %Thing objectAssoc: (%Thing, %List %Pair(%Thing,%Thing)) -> %Maybe %Pair(%Thing,%Thing) setDifference: (%List %Thing,%List %Thing) -> %List %Thing setUnion: (%List %Thing,%List %Thing) -> %List %Thing setIntersection: (%List %Thing,%List %Thing) -> %List %Thing atomic?: %Thing -> %Boolean finishLine: %Thing -> %Void firstNonblankPosition: (%String,%Short) -> %Maybe %Short firstBlankPosition: (%String,%Short) -> %Maybe %Short %defaultReadAndLoadSettings() --% ++ Return true if `x' is an atom of a quotation. atomic? x == x isnt [.,:.] or x.op is 'QUOTE --% membership operators objectMember?(x,l) == repeat l = nil => return false cons? l => sameObject?(x,first l) => return true l := rest l return sameObject?(x,l) symbolMember?(s,l) == repeat l = nil => return false cons? l => symbolEq?(s,first l) => return true l := rest l return symbolEq?(s,l) stringMember?(s,l) == repeat l = nil => return false cons? l => stringEq?(s,first l) => return true l := rest l return stringEq?(s,l) charMember?(c,l) == repeat l = nil => return false cons? l => charEq?(c,first l) => return true l := rest l return charEq?(c,l) scalarMember?(s,l) == repeat l = nil => return false cons? l => scalarEq?(s,first l) => return true l := rest l return scalarEq?(s,l) listMember?(x,l) == repeat l = nil => return false cons? l => listEq?(x,first l) => return true l := rest l return listEq?(x,l) --% list reversal reverse l == r := nil repeat cons? l => r := [first l,:r] l := rest l return r reverse! l == l1 := nil repeat cons? l => l2 := rest l l.rest := l1 l1 := l l := l2 return l1 --% return a pointer to the last cons-cell in the list `l'. lastNode l == while l is [.,:l'] and cons? l' repeat l := l' l --% list copying copyList l == not cons? l => l l' := t := [first l] repeat l := rest l cons? l => t.rest := [first l] t := rest t t.rest := l return l' --% append append!(x,y) == x = nil => y y = nil => x lastNode(x).rest := y x append(x,y) == append!(copyList x,y) --% a-list assocSymbol(s,al) == repeat al is [x,:al] => cons? x and symbolEq?(s,first x) => return x return nil --% substitution substitute!(y,x,s) == s = nil => nil sameObject?(x,s) => y if cons? s then s.first := substitute!(y,x,first s) s.rest := substitute!(y,x,rest s) s substitute(y,x,s) == s = nil => nil sameObject?(x,s) => y cons? s => h := substitute(y,x,first s) t := substitute(y,x,rest s) sameObject?(h,first s) and sameObject?(t,rest s) => s [h,:t] s applySubst(sl,t) == cons? t => hd := applySubst(sl,first t) tl := applySubst(sl,rest t) sameObject?(hd,first t) and sameObject?(tl,rest t) => t [hd,:tl] symbol? t and (p := assocSymbol(t,sl)) => rest p t applySubst!(sl,t) == cons? t => hd := applySubst!(sl,first t) tl := applySubst!(sl,rest t) t.first := hd t.rest := tl symbol? t and (p := assocSymbol(t,sl)) => rest p t ++ Like applySubst, but skip quoted materials. applySubstNQ(sl,t) == t is [hd,:tl] => hd is 'QUOTE => t hd := applySubstNQ(sl,hd) tl := applySubstNQ(sl,tl) sameObject?(hd,first t) and sameObject?(tl,rest t) => t [hd,:tl] symbol? t and (p := assocSymbol(t,sl)) => rest p t --% set operations setDifference(x,y) == x = nil => nil y = nil => x l := p := [nil] for [a,:.] in tails x | not objectMember?(a,y) repeat p.rest := [a] p := rest p rest l ++ Return the union of two lists of objects, with no duplicates. setUnion(x,y) == z := nil for a in x | not objectMember?(a,z) repeat z := [a,:z] for a in y | not objectMember?(a,z) repeat z := [a,:z] reverse! z ++ Return the intersection of two lists of objects, with no duplicates. setIntersection(x,y) == [a for a in x | objectMember?(a,y)] --% removal removeSymbol(l,x) == before := nil l' := l repeat not cons? l' => return l [y,:l'] := l' symbolEq?(x,y) => return append!(reverse! before,l') before := [y,:before] removeScalar(l,x) == before := nil l' := l repeat not cons? l' => return l [y,:l'] := l' scalarEq?(x,y) => return append!(reverse! before,l') before := [y,:before] removeValue(l,x) == before := nil l' := l repeat not cons? l' => return l [y,:l'] := l' valueEq?(x,y) => return append!(reverse! before,l') before := [y,:before] remove(l,x) == symbol? x => removeSymbol(l,x) char? x or integer? x => removeScalar(l,x) removeValue(l,x) --% search objectAssoc(x,l) == repeat l isnt [p,:l] => return nil p is [a,:.] and sameObject?(a,x) => return p ++ Return the index of the character `c' in the string `s', if present. ++ Otherwise, return nil. charPosition(c,s,k) == n := # s repeat k >= n => return nil stringChar(s,k) = c => return k k := k + 1 firstNonblankPosition(s,k) == or/[i for i in k..#s - 1 | stringChar(s,i) ~= char " "] firstBlankPosition(s,k) == or/[i for i in k..#s - 1 | stringChar(s,i) = char " "] --% I/O ++ Add a newline character and flush the output stream. finishLine out == writeNewline out flushOutput out