Sugar and prelude extension

1 files changed, 81 insertions, 27 deletions

diff --git a/prelude.cpp b/prelude.cpp
index cd51cad..5738844 100644
--- a/prelude.cpp
+++ b/prelude.cpp
@@ -3,6 +3,7 @@
 #include <string>
 #include "error.h"
 #include "prelude.h"
+#include "sugar.h"
 
 using namespace std;
 
@@ -15,7 +16,8 @@ const AST afterBootstrap=AST(R"RAW(
 	(def 'flip \f \a \b (f b a))
 	(def 'id \x x)
 	(def 'const \x \y x)
-	(def 'print (. putstr repr)))
+	(def 'print (. putstr repr))
+	(def '$ \f \x (f x)))
 )RAW");
 
 static AST dofunction(const AST&);
@@ -36,23 +38,14 @@ public:
 			return AST::makeString(res);
 		}));
 
-		intoEnv.define("putstr",AST::makeNative([](const AST &ast) -> AST {
-			if(ast.type!=AST::Type::string){
-				throw TypeError("Argument to 'putstr' is not a String");
-			}
-			cout<<ast.strval<<endl;
-			return AST();
-		}));
+		intoEnv.define("putstr",checkedHook("putstr",{AST::Type::string},
+			[](Environment&,const AST &ast) -> AST {cout<<ast.strval<<endl; return AST();}));
 
-		intoEnv.define("def",[](Environment &env,const AST &arg1) -> AST {
-			return AST::makeNative([&env,arg1](const AST &arg2) -> AST {
-				if(arg1.type!=AST::Type::name){
-					throw TypeError("First argument to 'def' is not a Name");
-				}
+		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);
 
@@ -62,18 +55,79 @@ public:
 			return res;
 		}));
 
-		intoEnv.define2("+",[](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 if(arg1.type==AST::Type::string){
-				return AST::makeString(arg1.strval+arg2.strval);
-			} else {
-				throw TypeError("Arguments to '+' neither Number nor String");
-			}
-		});
+		intoEnv.define("head",checkedHook("head",{AST::Type::tuple},
+			[](Environment&,const AST &arg) -> AST {
+				if(arg.terms.size()==0){
+					throw FormError("Empty tuple in 'head'");
+				}
+				return arg.terms[0];
+			}));
+
+		intoEnv.define("tail",checkedHook("tail",{AST::Type::tuple},
+			[](Environment&,const AST &arg) -> AST {
+				if(arg.terms.size()==0){
+					throw FormError("Empty tuple in 'tail'");
+				}
+				return AST::makeTuple(Terms(arg.terms.begin()+1,arg.terms.end()));
+			}));
+
+		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},{},{},
+			[](Environment&,const AST &arg1,const AST &arg2,const AST &arg3) -> AST {
+				if(arg1.numval!=0){
+					return arg2;
+				} else {
+					return arg3;
+				}
+			}));
+
+		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);
 	}