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#include <iostream>
#include <sstream>
#include <string>
#include "error.h"
#include "prelude.h"
#include "sugar.h"
using namespace std;
Environment prelude;
const AST afterBootstrap=AST(R"RAW(
(do
(def '. \f \g \x (f (g x)))
(def 'flip \f \a \b (f b a))
(def 'id \x x)
(def 'const \x \y x)
(def 'print (. putstr repr))
(def '$ \f \x (f x))
(def 'if \c \t \f (__if c (() t) (() f)))
(def 'last \l (if (nil (tail l)) (head l) (last (tail l)))))
)RAW");
static AST dofunction(const AST&);
const AST doNative=AST::makeNative(dofunction);
static AST dofunction(const AST&){
return doNative;
}
class PreludeInit{
public:
PreludeInit(Environment &intoEnv){
intoEnv.define("repr",AST::makeNative([](const AST &ast) -> AST {
stringstream ss;
ss<<ast;
String res=ss.str();
return AST::makeString(res);
}));
intoEnv.define("putstr",checkedHook("putstr",{AST::Type::string},
[](Environment&,const AST &ast) -> AST {cout<<ast.strval<<endl; return AST();}));
intoEnv.define("def",checkedHook("def",{AST::Type::name},{},
[](Environment &env,const AST &arg1,const AST &arg2) -> AST {
env.define(arg1.nameval,arg2);
return AST();
}));
intoEnv.define("do",doNative);
intoEnv.define("unquote",AST::makeNative([](const AST &ast) -> AST {
AST res(ast);
res.quoted=false;
return res;
}));
intoEnv.define("head",checkedHook("head",{AST::Type::tuple},
[](Environment&,const AST &arg) -> AST {
if(arg.terms.size()==0){
throw FormError("Empty tuple in 'head'");
}
AST res=arg.terms[0];
if(arg.quoted){
res.quoted=true;
}
return res;
}));
intoEnv.define("tail",checkedHook("tail",{AST::Type::tuple},
[](Environment&,const AST &arg) -> AST {
if(arg.terms.size()==0){
throw FormError("Empty tuple in 'tail'");
}
AST res=AST::makeTuple(Terms(arg.terms.begin()+1,arg.terms.end()));
if(arg.quoted){
res.quoted=true;
}
return res;
}));
intoEnv.define("nil",checkedHook("nil",{AST::Type::tuple},
[](Environment&,const AST &arg) -> AST {
return AST::makeNumber(arg.terms.size()==0);
}));
intoEnv.define("not",checkedHook("not",{AST::Type::number},
[](Environment&,const AST &arg) -> AST {
return AST::makeNumber(arg.numval==0);
}));
intoEnv.define("__if",checkedHook("__if",{AST::Type::number},{AST::Type::tuple},{AST::Type::tuple},
[](Environment&,const AST &arg1,const AST &arg2,const AST &arg3) -> AST {
if(arg2.terms.size()!=2||arg3.terms.size()!=2){
throw FormError("Then and else arguments to '__if' should be 2-tuples with value in second element");
}
const AST &choice=arg1.numval!=0?arg2:arg3;
AST res=choice.terms[1];
if(choice.quoted){
res.quoted=true;
}
return res;
}));
intoEnv.define("+",checkedHook("+",{AST::Type::number,AST::Type::string},
{AST::Type::number,AST::Type::string},
[](Environment&,const AST &arg1,const AST &arg2) -> AST {
if(arg1.type!=arg2.type){
throw TypeError("Unequal types in '+'");
}
if(arg1.type==AST::Type::number){
return AST::makeNumber(arg1.numval+arg2.numval);
} else {
return AST::makeString(arg1.strval+arg2.strval);
}
}));
intoEnv.define("-",checkedHook("-",{AST::Type::number},{AST::Type::number},
[](Environment&,const AST &arg1,const AST &arg2) -> AST {
return AST::makeNumber(arg1.numval-arg2.numval);
}));
intoEnv.define("*",checkedHook("*",{AST::Type::number},{AST::Type::number},
[](Environment&,const AST &arg1,const AST &arg2) -> AST {
return AST::makeNumber(arg1.numval*arg2.numval);
}));
intoEnv.define("/",checkedHook("/",{AST::Type::number},{AST::Type::number},
[](Environment&,const AST &arg1,const AST &arg2) -> AST {
return AST::makeNumber(arg1.numval/arg2.numval);
}));
intoEnv.define("%",checkedHook("%",{AST::Type::number},{AST::Type::number},
[](Environment&,const AST &arg1,const AST &arg2) -> AST {
return AST::makeNumber(arg1.numval%arg2.numval);
}));
intoEnv.define("=",checkedHook("=",{AST::Type::number,AST::Type::string},
{AST::Type::number,AST::Type::string},
[](Environment&,const AST &arg1,const AST &arg2) -> AST {
return AST::makeNumber(arg1.type==arg2.type&&arg1.numval==arg2.numval);
}));
intoEnv.run(afterBootstrap);
}
} preludeInit(prelude);
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