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|
-- Copyright (c) 1991-2002, The Numerical Algorithms Group Ltd.
-- All rights reserved.
-- Copyright (C) 2007-2011, 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.
import macros
namespace BOOT
module postpar
++ The type of parse trees.
%ParseTree <=>
%Number or %Symbol or %String or %Pair(%Thing,%Thing)
++ The result of processing a parse tree.
%ParseForm <=>
%Number or %Symbol or %String or %Pair(%Thing,%Thing)
$postStack := []
--% Yet Another Parser Transformation File
--These functions are used by for BOOT and SPAD code
--(see new2OldLisp, e.g.)
postTransform: %ParseTree -> %ParseForm
postTransform y ==
x:= y
u:= postTran x
if u is ["%Comma",:l,[":",y,t]] and (and/[IDENTP x for x in l]) then u:=
[":",["LISTOF",:l,y],t]
postTransformCheck u
u
displayPreCompilationErrors() ==
n:= #($postStack:= removeDuplicates reverse! $postStack)
n=0 => nil
errors:=
1<n => '"errors"
'"error"
if $InteractiveMode
then sayBrightly ['" Semantic ",errors,'" detected: "]
else
heading:=
$topOp ~= '$topOp => ['" ",$topOp,'" has"]
['" You have"]
sayBrightly [:heading,'"%b",n,'"%d",'"precompilation ",errors,'":"]
if 1<n then
(for x in $postStack for i in 1.. repeat sayMath ['" ",i,'"_) ",:x])
else sayMath ['" ",:first $postStack]
TERPRI()
postTran: %ParseTree -> %ParseForm
postTran x ==
atom x =>
postAtom x
op := first x
symbol? op and (f:= property(op,'postTran)) => FUNCALL(f,x)
op is ["elt",a,b] =>
u:= postTran [b,:rest x]
[postTran op,:rest u]
op is ["Scripts",:.] =>
postScriptsForm(op,"append"/[unComma postTran y for y in rest x])
op ~= (y:= postOp op) => [y,:postTranList rest x]
postForm x
postTranList: %List %ParseTree -> %List %ParseForm
postTranList x ==
[postTran y for y in x]
postBigFloat: %ParseTree -> %ParseTree
postBigFloat x ==
[.,mant,:expon] := x
eltword := if $InteractiveMode then "$elt" else "elt"
postTran [[eltword,$Float,"float"],[",",[",",mant,expon],10]]
postAdd: %ParseTree -> %ParseForm
postAdd x ==
x isnt ["add",a,:b] => systemErrorHere ["postAdd",x]
b=nil => postCapsule a
["add",postTran a,postCapsule first b]
checkWarning: %Thing -> %Thing
checkWarning msg ==
postError concat('"Parsing error: ",msg)
checkWarningIndentation: () -> %Thing
checkWarningIndentation() ==
checkWarning ['"Apparent indentation error following",:bright "add"]
postCapsule: %ParseTree -> %ParseForm
postCapsule x ==
x isnt [op,:.] => checkWarningIndentation()
integer? op or op = "==" => ["CAPSULE",postBlockItem x]
op = ";" => ["CAPSULE",:postBlockItemList postFlatten(x,";")]
op = "if" => ["CAPSULE",postBlockItem x]
checkWarningIndentation()
postQUOTE: %ParseTree -> %ParseForm
postQUOTE x ==
x
postColon: %ParseTree -> %ParseForm
postColon u ==
u is [":",x] => [":",postTran x]
u is [":",x,y] => [":",postTran x,:postType y]
postAtSign: %ParseTree -> %ParseForm
postAtSign t ==
t isnt ["@",x,y] => systemErrorHere ["postAtSign",t]
["@",postTran x,:postType y]
postPretend: %ParseTree -> %ParseForm
postPretend t ==
t isnt ["pretend",x,y] => systemErrorHere ["postPretend",t]
["pretend",postTran x,:postType y]
postConstruct: %ParseTree -> %ParseForm
postConstruct u ==
u is ["construct",b] =>
a:= (b is [",",:.] => ["%Comma",:postFlatten(b,",")]; b)
a is ["SEGMENT",p,q] => ["construct",postTranSegment(p,q)]
a is ["%Comma",:l] =>
or/[x is [":",y] for x in l] => postMakeCons l
or/[x is ["SEGMENT",:.] for x in l] => tuple2List l
["construct",:postTranList l]
["construct",postTran a]
u
postError: %Thing -> %Thing
postError msg ==
BUMPERRORCOUNT 'precompilation
xmsg:=
$defOp ~= nil and not $InteractiveMode => [$defOp,'": ",:msg]
msg
$postStack:= [xmsg,:$postStack]
nil
postMakeCons: %ParseTree -> %ParseForm
postMakeCons l ==
null l => "nil"
l is [[":",a],:l'] =>
l' => ["append",postTran a,postMakeCons l']
postTran a
["cons",postTran first l,postMakeCons rest l]
postAtom: %Atom -> %ParseForm
postAtom x ==
x=0 => $Zero
x=1 => $One
x='T => "T$" -- rename T in spad code to T$
IDENTP x and niladicConstructorFromDB x => [x]
x="," => "%Comma"
x = "^" => "**" -- always use `**' internally for exponentiation
x
postBlock: %ParseTree -> %ParseForm
postBlock t ==
t isnt ["%Block",:l,x] => systemErrorHere ["postBlock",t]
["SEQ",:postBlockItemList l,["exit",postTran x]]
postBlockItemList: %List %ParseTree -> %List %ParseTree
postBlockItemList l ==
[postBlockItem x for x in l]
postBlockItem: %ParseTree -> %ParseForm
postBlockItem x ==
x:= postTran x
x is ["%Comma",:l,[":",y,t]] and (and/[IDENTP x for x in l]) =>
[":",["LISTOF",:l,y],t]
x
postCategory: %ParseTree -> %ParseForm
postCategory u ==
u isnt ["CATEGORY",:l] => systemErrorHere ["postCategory",u]
--RDJ: ugh_ please -- someone take away need for PROGN as soon as possible
null l => u
op :=
$insidePostCategoryIfTrue = true => "PROGN"
"CATEGORY"
[op,:[fn x for x in l]] where fn x ==
$insidePostCategoryIfTrue: local := true
postTran x
postComma: %ParseTree -> %ParseForm
postComma u ==
post%Comma ["%Comma",:postFlatten(u,",")]
postDef: %ParseTree -> %ParseForm
postDef t ==
t isnt [defOp,lhs,rhs] => systemErrorHere ["postDef",t]
lhs is ['macro,name] => postMDef ["==>",name,rhs]
recordHeaderDocumentation nil
if $maxSignatureLineNumber ~= 0 then
$docList := [["constructor",:$headerDocumentation],:$docList]
$maxSignatureLineNumber := 0
--reset this for next constructor; see recordDocumentation
lhs:= postTran lhs
[form,targetType]:=
lhs is [":",:.] => rest lhs
[lhs,nil]
if not $InteractiveMode and atom form then form := [form]
newLhs:=
atom form => form
[op,:argl]:= [(x is [":",a,.] => a; x) for x in form]
[op,:postDefArgs argl]
argTypeList:=
atom form => nil
[(x is [":",.,t] => t; nil) for x in rest form]
typeList:= [targetType,:argTypeList]
if atom form then form := [form]
specialCaseForm := [nil for x in form]
["DEF",newLhs,typeList,specialCaseForm,postTran rhs]
postDefArgs: %List %ParseTree -> %List %ParseForm
postDefArgs argl ==
null argl => argl
argl is [[":",a],:b] =>
b ~= nil => postError
['" Argument",:bright a,'"of indefinite length must be last"]
atom a or a is ["QUOTE",:.] => a
postError
['" Argument",:bright a,'"of indefinite length must be a name"]
[first argl,:postDefArgs rest argl]
postMDef: %ParseTree -> %ParseForm
postMDef(t) ==
[.,lhs,rhs] := t
$InteractiveMode =>
lhs := postTran lhs
not IDENTP lhs => throwKeyedMsg("S2IP0001",nil)
["MDEF",lhs,nil,nil,postTran rhs]
lhs:= postTran lhs
[form,targetType]:=
lhs is [":",:.] => rest lhs
[lhs,nil]
form:=
atom form => [form]
form
newLhs:= [(x is [":",a,:.] => a; x) for x in form]
typeList:= [targetType,:[(x is [":",.,t] => t; nil) for x in rest form]]
["MDEF",newLhs,typeList,[nil for x in form],postTran rhs]
postElt: %ParseTree -> %ParseForm
postElt u ==
u isnt [.,a,b] => systemErrorHere ["postElt",u]
a:= postTran a
b is ["%Sequence",:.] => [["elt",a,"makeRecord"],:postTranList rest b]
["elt",a,postTran b]
postExit: %ParseTree -> %ParseForm
postExit t ==
t isnt ["=>",a,b] => systemErrorHere ["postExit",t]
["IF",postTran a,["exit",postTran b],"%noBranch"]
postFlatten: (%ParseTree, %Symbol) -> %ParseForm
postFlatten(x,op) ==
x is [ =op,a,b] => [:postFlatten(a,op),:postFlatten(b,op)]
[x]
postForm: %ParseTree -> %ParseForm
postForm u ==
u isnt [op,:argl] => systemErrorHere ["postForm",u]
x:=
atom op =>
argl':= postTranList argl
op':=
true=> op
GETL(op,'Led) or GETL(op,'Nud) or op = 'IN => op
numOfArgs:= (argl' is [["%Comma",:l]] => #l; 1)
INTERNL("*",STRINGIMAGE numOfArgs,PNAME op)
[op',:argl']
op is ["Scripts",:.] => [:postTran op,:postTranList argl]
u:= postTranList u
if u is [["%Comma",:.],:.] then
postError ['" ",:bright u,
'"is illegal because tuples cannot be applied!",'"%l",
'" Did you misuse infix dot?"]
u
x is [.,["%Comma",:y]] => [first x,:y]
x
postQuote: %ParseTree -> %ParseForm
postQuote [.,a] ==
["QUOTE",a]
postScriptsForm: (%ParseTree,%List %ParseTree) -> %ParseForm
postScriptsForm(t,argl) ==
t isnt ["Scripts",op,a] => systemErrorHere ["postScriptsForm",t]
[getScriptName(op,a,#argl),:postTranScripts a,:argl]
postScripts: %ParseTree -> %ParseForm
postScripts t ==
t isnt ["Scripts",op,a] => systemErrorHere ["postScripts",t]
[getScriptName(op,a,0),:postTranScripts a]
getScriptName: (%Symbol,%ParseTree, %Short) -> %ParseForm
getScriptName(op,a,numberOfFunctionalArgs) ==
if not IDENTP op then
postError ['" ",op,'" cannot have scripts"]
INTERNL("*",STRINGIMAGE numberOfFunctionalArgs,
decodeScripts a,symbolName op)
postTranScripts: %ParseTree -> %ParseForm
postTranScripts a ==
a is ["PrefixSC",b] => postTranScripts b
a is [";",:b] => "append"/[postTranScripts y for y in b]
a is [",",:b] =>
("append"/[fn postTran y for y in b]) where
fn x ==
x is ["%Comma",:y] => y
[x]
[postTran a]
decodeScripts: %ParseTree -> %ParseForm
decodeScripts a ==
a is ["PrefixSC",b] => strconc(STRINGIMAGE 0,decodeScripts b)
a is [";",:b] => APPLX(function strconc,[decodeScripts x for x in b])
a is [",",:b] =>
STRINGIMAGE fn a where fn a == (a is [",",:b] => +/[fn x for x in b]; 1)
STRINGIMAGE 1
postIf: %ParseTree -> %ParseForm
postIf t ==
t isnt ["if",:l] => t
["IF",:[(null (x:= postTran x) => "%noBranch"; x)
for x in l]]
postJoin: %ParseTree -> %ParseForm
postJoin ["Join",a,:l] ==
a:= postTran a
l:= postTranList l
if l is [b] and b is [name,:.] and name in '(ATTRIBUTE SIGNATURE) then l
:= [["CATEGORY",b]]
al:=
a is ["%Comma",:c] => c
[a]
["Join",:al,:l]
postMapping: %ParseTree -> %ParseForm
postMapping u ==
u isnt ["->",source,target] => u
["Mapping",postTran target,:unComma postTran source]
postOp: %ParseTree -> %ParseForm
postOp x ==
x=":=" => "%LET"
x=":-" => "LETD"
x="%Attribute" => "ATTRIBUTE"
x
postRepeat: %ParseTree -> %ParseForm
postRepeat t ==
t isnt ["REPEAT",:m,x] => systemErrorHere ["postRepeat",t]
["REPEAT",:postIteratorList m,postTran x]
postSEGMENT: %ParseTree -> %ParseForm
postSEGMENT t ==
t isnt ["SEGMENT",a,b] => systemErrorHere ["postSEGMENT",t]
key:= [a,'"..",:(b => [b]; nil)]
postError ['" Improper placement of segment",:bright key]
postCollect: %ParseTree -> %ParseForm
postCollect t ==
t isnt [constructOp,:m,x] => systemErrorHere ["postCollect",t]
x is [["elt",D,"construct"],:y] =>
postCollect [["elt",D,"COLLECT"],:m,["construct",:y]]
itl:= postIteratorList m
x:= (x is ["construct",r] => r; x) --added 84/8/31
y:= postTran x
finish(constructOp,itl,y) where
finish(op,itl,y) ==
y is [":",a] => ["REDUCE","append",0,[op,:itl,a]]
y is ["%Comma",:l] =>
newBody:=
or/[x is [":",y] for x in l] => postMakeCons l
or/[x is ["SEGMENT",:.] for x in l] => tuple2List l
["construct",:postTranList l]
["REDUCE","append",0,[op,:itl,newBody]]
[op,:itl,y]
postTupleCollect: %ParseTree -> %ParseForm
postTupleCollect t ==
t isnt [constructOp,:m,x] => systemErrorHere ["postTupleCollect",t]
postCollect [constructOp,:m,["construct",x]]
postIteratorList: %List %ParseTree -> %List %ParseForm
postIteratorList x ==
x is [p,:l] =>
(p:= postTran p) is ["IN",y,u] =>
u is ["|",a,b] => [["IN",y,postInSeq a],["|",b],:postIteratorList l]
[["IN",y,postInSeq u],:postIteratorList l]
[p,:postIteratorList l]
x
postin: %ParseTree -> %ParseForm
postin arg ==
arg isnt ["in",i,seq] => systemErrorHere ["postin",arg]
["in",postTran i, postInSeq seq]
postIn: %ParseTree -> %ParseForm
postIn arg ==
arg isnt ["IN",i,seq] => systemErrorHere ["postIn",arg]
["IN",postTran i,postInSeq seq]
postInSeq: %ParseTree -> %ParseForm
postInSeq seq ==
seq is ["SEGMENT",p,q] => postTranSegment(p,q)
seq is ["%Comma",:l] => tuple2List l
postTran seq
postTranSegment: (%ParseTree, %ParseTree) -> %ParseForm
postTranSegment(p,q) ==
["SEGMENT",postTran p,(q => postTran q; nil)]
tuple2List: %ParseTree -> %ParseForm
tuple2List l ==
l is [a,:l'] =>
u:= tuple2List l'
a is ["SEGMENT",p,q] =>
null u => ["construct",postTranSegment(p,q)]
$InteractiveMode =>
["append",["construct",postTranSegment(p,q)],tuple2List l']
["nconc",["construct",postTranSegment(p,q)],tuple2List l']
null u => ["construct",postTran a]
["cons",postTran a,tuple2List l']
nil
SEGMENT: %ParseTree -> %ParseForm
SEGMENT(a,b) ==
[i for i in a..b]
postReduce: %ParseTree -> %ParseForm
postReduce t ==
t isnt ["%Reduce",op,expr] => systemErrorHere ["postReduce",t]
$InteractiveMode or expr is ["COLLECT",:.] =>
["REDUCE",op,0,postTran expr]
postReduce ["%Reduce",op,["COLLECT",["IN",g:= gensym(),expr],
["construct", g]]]
postFlattenLeft: (%ParseTree, %Symbol) -> %ParseForm
postFlattenLeft(x,op) ==--
x is [ =op,a,b] => [:postFlattenLeft(a,op),b]
[x]
postSemiColon: %ParseTree -> %ParseForm
postSemiColon u ==
postBlock ["%Block",:postFlattenLeft(u,";")]
postSequence: %ParseTree -> %ParseForm
postSequence t ==
t isnt ["%Sequence",:l] => systemErrorHere ["postSequence",t]
['(elt $ makeRecord),:postTranList l]
postSignature: %ParseTree -> %ParseForm
postSignature t ==
t isnt ["%Signature",op,sig] => systemErrorHere ["postSignature",t]
sig is ["->",:.] =>
sig1:= postType sig
op:= postAtom (string? op => makeSymbol op; op)
["SIGNATURE",op,:removeSuperfluousMapping killColons sig1]
["SIGNATURE",postAtom op,:postType ["->","constant",sig]]
killColons: %ParseTree -> %ParseForm
killColons x ==
atom x => x
x is [op,:.] and op in '(Record Union %Forall %Exist) => x
x is [":",.,y] => killColons y
[killColons first x,:killColons rest x]
postSlash: %ParseTree -> %ParseForm
postSlash t ==
t isnt ['_/,a,b] => systemErrorHere ["postSlash",t]
string? a => postTran ["%Reduce",makeSymbol a,b]
['_/,postTran a,postTran b]
removeSuperfluousMapping: %ParseTree -> %ParseForm
removeSuperfluousMapping sig1 ==
--get rid of this asap
sig1 is [x,:y] and x is ["Mapping",:.] => [rest x,:y]
sig1
postType: %ParseTree -> %ParseForm
postType typ ==
typ is ["->",source,target] =>
source="constant" => [[postTran target],"constant"]
[["Mapping",postTran target,:unComma postTran source]]
typ is ["->",target] => [["Mapping",postTran target]]
[postTran typ]
post%Comma: %ParseTree -> %ParseForm
post%Comma u ==
u is ["%Comma"] => u
u is ["%Comma",:l,a] => (["%Comma",:postTranList rest u])
--u is ["%Comma",:l,a] => (--a:= postTran a; ["%Comma",:postTranList rest u])
--RDJ: don't understand need for above statement that is commented out
postWhere: %ParseTree -> %ParseForm
postWhere t ==
t isnt ["where",a,b] => systemErrorHere ["postWhere",t]
x:=
b is ["%Block",:c] => c
[b]
["where",postTran a,:postTranList x]
postWith: %ParseTree -> %ParseForm
postWith t ==
t isnt ["with",a] => systemErrorHere ["postWidth",t]
$insidePostCategoryIfTrue: local := true
a:= postTran a
a is [op,:.] and op in '(SIGNATURE ATTRIBUTE IF) => ["CATEGORY",a]
a is ["PROGN",:b] => ["CATEGORY",:b]
a
postTransformCheck: %ParseTree -> %ParseForm
postTransformCheck x ==
$defOp: local:= nil
postcheck x
postcheck: %ParseTree -> %ParseForm
postcheck x ==
atom x => nil
x is ["DEF",form,[target,:.],:.] =>
setDefOp form
postcheck rest rest x
x is ["QUOTE",:.] => nil
postcheck first x
postcheck rest x
setDefOp: %ParseForm -> %Thing
setDefOp f ==
if f is [":",g,:.] then f := g
f := (atom f => f; first f)
if $topOp then $defOp:= f else $topOp:= f
unComma: %ParseForm -> %ParseForm
unComma x ==
x is ["%Comma",:y] => y
[x]
--% `^='
++ check that `^=' is not used in Spad code to mean `not equal'.
postBootNotEqual: %ParseTree -> %ParseForm
postBootNotEqual u ==
checkWarning ['"Operator ", :bright '"^=",
'"is not valid Spad. Please use",:bright '"~=",'"instead."]
["~=",:postTran rest u]
--% %Match
postAlternatives alts ==
alts is ["%Block",:cases] => ["%Block",:[tranAlt c for c in cases]]
tranAlt alts
where
tranAlt c ==
c is ["=>",pred,conseq] =>
["=>",postTran pred,postTran conseq]
postTran c
postMatch: %ParseTree -> %ParseForm
postMatch t ==
t isnt ["%Match",expr,alts] => systemErrorHere ["postMatch",t]
alts :=
alts is [";",:.] => ["%Block",:postFlattenLeft(alts,";")]
alts
["%Match",postTran expr, postAlternatives alts]
--% Register special parse tree tranformers.
for x in [["with", :"postWith"],_
["Scripts", :"postScripts"],_
["/", :"postSlash"],_
["construct", :"postConstruct"],_
["%Block", :"postBlock"],_
["QUOTE", :"postQUOTE"],_
["COLLECT", :"postCollect"],_
[":BF:", :"postBigFloat"],_
["in", :"postin"],_
["IN", :"postIn"],_
["REPEAT", :"postRepeat"],_
["TupleCollect", :"postTupleCollect"],_
["add", :"postAdd"],_
["%Reduce", :"postReduce"],_
[",", :"postComma"],_
[";", :"postSemiColon"],_
["where", :"postWhere"],_
[":", :"postColon"],_
["@", :"postAtSign"],_
["pretend", :"postPretend"],_
["if", :"postIf"],_
["Join", :"postJoin"],_
["%Signature", :"postSignature"],_
["CATEGORY", :"postCategory"],_
["==", :"postDef"],_
["==>", :"postMDef"],_
["->", :"postMapping"],_
["=>", :"postExit"],_
["%Match",:"postMatch"],_
["^=", :"postBootNotEqual"],_
["%Comma", :"post%Comma"]] repeat
property(first x, 'postTran) := rest x
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