Add more error messages

source/err/errorfile.go

@@ -1225,12 +1225,45 @@ var ErrorCreatorMap = map[string]ErrorCreator{
 		},
 	},
 
-	"init/assign/ident": {
+	"init/assign": {
 		Message: func(tok *token.Token, args ...any) string {
-			return "left-hand side of assignment should be identifier"
+			return "expected assignment"
 		},
 		Explanation: func(errors Errors, pos int, tok *token.Token, args ...any) string {
-			return "The left-hand side of an assignment operation names the things to be assigned to."
+			return "All you're meant to do in the 'var' and 'const' sections of " +
+			       "the code is assign variables and constants, respectively"
+		},
+	},
+
+	"init/clone/comma": {
+		Message: func(tok *token.Token, args ...any) string {
+			return "expected comma-separated list"
+		},
+		Explanation: func(errors Errors, pos int, tok *token.Token, args ...any) string {
+			return "When declaring a clone type, after 'using', Pipefish expects a comma-" +
+			       "separated list of operations that the type can use."
+		},
+	},
+
+	"init/clone/type": {
+		Message: func(tok *token.Token, args ...any) string {
+			return "can't clone type " + emph(args[0])
+		},
+		Explanation: func(errors Errors, pos int, tok *token.Token, args ...any) string {
+			return "Only the types 'float', 'int', 'list', 'map', 'pair', 'rune', " +
+			       "'set' and 'string' are cloneable."
+		},
+	},
+
+	"init/clone/using": {
+		Message: func(tok *token.Token, args ...any) string {
+			return "was expecting end of line or 'using' keyword"
+		},
+		Explanation: func(errors Errors, pos int, tok *token.Token, args ...any) string {
+			return "When defining a clone type, after giving the type of its parent " +
+			"you've either finished, or you can go on to request operations for it, which "+
+			"consists of the word 'using' followed by a comma-separated list of the " +
+			"operations you want to use."
 		},
 	},
 
@@ -1249,6 +1282,25 @@ var ErrorCreatorMap = map[string]ErrorCreator{
 		},
 	},
 
+	"init/depend/cmd": {
+		Message: func(tok *token.Token, args ...any) string {
+			return "illegal dependency on command"
+		},
+		Explanation: func(errors Errors, pos int, tok *token.Token, args ...any) string {
+			return  "Only a command can use another command as a dependency."
+		},
+	},
+
+	"init/depend/var": {
+		Message: func(tok *token.Token, args ...any) string {
+			return "illegal dependency on global variable"
+		},
+		Explanation: func(errors Errors, pos int, tok *token.Token, args ...any) string {
+			return  "Only a command or another variable declaration can use another " +
+			        "variable as a dependency."
+		},
+	},
+
 	"init/enum/comma": {
 		Message: func(tok *token.Token, args ...any) string {
 			return "expected comma, got " + text.DescribeTok(tok)
@@ -1308,6 +1360,16 @@ var ErrorCreatorMap = map[string]ErrorCreator{
 		},
 	},
 
+	"init/external/file": {
+		Message: func(tok *token.Token, args ...any) string {
+			return "failed to open file " + emph(args[0]) + " with error " + emph(args[1])
+		},
+		Explanation: func(errors Errors, pos int, tok *token.Token, args ...any) string {
+			return "This error very much means what it says. Pipefish tried to open the file " +
+			       "specified in the 'external' statement, and failed."
+		},
+	},
+
 	"init/external/path/a": {
 		Message: func(tok *token.Token, args ...any) string {
 			return "malformed path to external service"
@@ -1440,6 +1502,57 @@ var ErrorCreatorMap = map[string]ErrorCreator{
 		},
 	},
 
+	"init/interface/colon": {
+		Message: func(tok *token.Token, args ...any) string {
+			return "unexpected occurrence of " + emph(tok.Literal)
+		},
+		Explanation: func(errors Errors, pos int, tok *token.Token, args ...any) string {
+			return "The only thing Pipefish was expecting to see after 'interface' is a colon."
+		},
+	},
+
+	"init/interface/self": {
+		Message: func(tok *token.Token, args ...any) string {
+			return "'self' missing in clause of interface"
+		},
+		Explanation: func(errors Errors, pos int, tok *token.Token, args ...any) string {
+			return "The parts of an interface define what types fit it b referring to the " +
+			       "behavior of a pseudotype called 'self'. Any clause of this definition that " +
+				   "doesn't refer to 'self' would not in fact contribute to the definition of " +
+				   "the interface."
+		},
+	},
+
+	"init/name/exists/a": {
+		Message: func(tok *token.Token, args ...any) string {
+			return "definition of " + emph(args[1]) + text.DescribePos((args[0]).(*token.Token)) +
+			       " conflicts with definition"
+		},
+		Explanation: func(errors Errors, pos int, tok *token.Token, args ...any) string {
+			return "You can't declare the same identifier twice!"
+		},
+	},
+
+	"init/name/exists/b": {
+		Message: func(tok *token.Token, args ...any) string {
+			return "definition of " + emph(args[1]) + text.DescribePos((args[0]).(*token.Token)) +
+			       " conflicts with definition"
+		},
+		Explanation: func(errors Errors, pos int, tok *token.Token, args ...any) string {
+			return "You can't declare the same identifier twice!"
+		},
+	},
+
+	"init/name/exists/c": {
+		Message: func(tok *token.Token, args ...any) string {
+			return "definition of " + emph(args[1]) + text.DescribePos((args[0]).(*token.Token)) +
+			       " conflicts with definition"
+		},
+		Explanation: func(errors Errors, pos int, tok *token.Token, args ...any) string {
+			return "You can't declare the same identifier twice!"
+		},
+	},
+
 	"init/overload/a": {
 		Message: func(tok *token.Token, args ...any) string {
 			return "too much overloading: function '" + args[0].(string) + "' defined at@line " + strconv.Itoa(args[1].(int)) + "@conflicts with another version of the same function defined at"
@@ -1514,7 +1627,7 @@ var ErrorCreatorMap = map[string]ErrorCreator{
 			return "mismatching reference parameters in overloaded function"
 		},
 		Explanation: func(errors Errors, pos int, tok *token.Token, args ...any) string {
-			return "if you overload a function with reference parameters, then they must have the same number of reference parameters, at the start of the parameter list, or you will see this error."
+			return "If you overload a function with reference parameters, then they must have the same number of reference parameters, at the start of the parameter list, or you will see this error."
 		},
 	},
 
@@ -1542,21 +1655,90 @@ var ErrorCreatorMap = map[string]ErrorCreator{
 
 	"init/request/float": {
 		Message: func(tok *token.Token, args ...any) string {
-			return "clone of type " + emph("float") + " cannot request operation " + emph(args[0])
+			return "clone of " + emph("float") + " cannot request operation " + emph(args[0])
 		},
 		Explanation: func(errors Errors, pos int, tok *token.Token, args ...any) string {
-			return "A clone of " + emph("int") + " can only request the native operations suitable to that type, i.e. " +
+			return "A clone of " + emph("float") + " can only request the native operations suitable to that type, i.e. " +
 				emph("+") + ", " + emph("-") + ", " + emph("*") + ", and " + emph("/") + "."
 		},
 	},
 
 	"init/request/int": {
 		Message: func(tok *token.Token, args ...any) string {
-			return "clone of type " + emph("int") + " cannot request operation " + emph(args[0])
+			return "clone of " + emph("int") + " cannot request operation " + emph(args[0])
 		},
 		Explanation: func(errors Errors, pos int, tok *token.Token, args ...any) string {
 			return "A clone of " + emph("int") + " can only request the native operations suitable to that type, i.e. " +
-				emph("+") + ", " + emph("-") + ", " + emph("*") + ", " + emph("/") + ", and " + emph("%") + "."
+				emph("+") + ", " + emph("-") + ", " + emph("*") + emph("div") + ", " + ", and " + emph("mod") + "."
+		},
+	},
+
+	"init/request/list": {
+		Message: func(tok *token.Token, args ...any) string {
+			return "clone of " + emph("list") + " cannot request operation " + emph(args[0])
+		},
+		Explanation: func(errors Errors, pos int, tok *token.Token, args ...any) string {
+			return "A clone of " + emph("list") + " can only request the native operations suitable to that type, i.e. " +
+				emph("+") + ", " + emph("with") + ", " + emph("?>") + emph(">>") + ", " + ", and " + emph("slice") + "."
+		},
+	},
+
+	"init/request/map": {
+		Message: func(tok *token.Token, args ...any) string {
+			return "clone of " + emph("map") + " cannot request operation " + emph(args[0])
+		},
+		Explanation: func(errors Errors, pos int, tok *token.Token, args ...any) string {
+			return "A clone of " + emph("map") + " can only request the native operations suitable to that type, i.e. " +
+				emph("with") + " and " + emph("without") + "."
+		},
+	},
+
+	"init/request/pair": {
+		Message: func(tok *token.Token, args ...any) string {
+			return "clone of " + emph("pair") + " cannot request operations"
+		},
+		Explanation: func(errors Errors, pos int, tok *token.Token, args ...any) string {
+			return "Since the " + emph("pair") + " type has no native operations besides " +
+			       "indexing, which you get for free, there's nothing to request."
+		},
+	},
+
+	"init/request/set": {
+		Message: func(tok *token.Token, args ...any) string {
+			return "clone of " + emph("set") + " cannot request operation " + emph(args[0])
+		},
+		Explanation: func(errors Errors, pos int, tok *token.Token, args ...any) string {
+			return "A clone of " + emph("int") + " can only request the native operations suitable to that type, i.e. " +
+				emph("+") + " and " + emph("-") + "."
+		},
+	},
+
+	"init/request/string": {
+		Message: func(tok *token.Token, args ...any) string {
+			return "clone of " + emph("string") + " cannot request operation " + emph(args[0])
+		},
+		Explanation: func(errors Errors, pos int, tok *token.Token, args ...any) string {
+			return "A clone of " + emph("string") + " can only request the native operations suitable to that type, i.e. " +
+				emph("+") + " and " + emph("slice") + "."
+		},
+	},
+
+	"init/service/depends": {
+		Message: func(tok *token.Token, args ...any) string {
+			return "service variable " + emph(args[0]) + " has illegal dependencies"
+		},
+		Explanation: func(errors Errors, pos int, tok *token.Token, args ...any) string {
+			return "As service variables are initialized before anything else, they shouldn't" +
+			       "depend on anything else you define in your code."
+		},
+	},
+
+	"init/service/type": {
+		Message: func(tok *token.Token, args ...any) string {
+			return "service variable " + emph(args[0]) + " should have type " + emph(args[1])
+		},
+		Explanation: func(errors Errors, pos int, tok *token.Token, args ...any) string {
+			return "The fact that you can redeclare service variables doesn't mean you can change their type."
 		},
 	},
 
@@ -1641,12 +1823,12 @@ var ErrorCreatorMap = map[string]ErrorCreator{
 		},
 	},
 
-	"init/type/null": {
+	"init/type/defined": {
 		Message: func(tok *token.Token, args ...any) string {
-			return "type name ends in " + emph("?")
+			return "redefinition of type"
 		},
 		Explanation: func(errors Errors, pos int, tok *token.Token, args ...any) string {
-			return "Only an abstract type name can end in " + emph("?") + ", and even then only if the type contains " + emph("NULL") + "."
+			return "Each type can only be declared once."
 		},
 	},
 

source/initializer/initializer.go

@@ -451,7 +451,7 @@ func (iz *initializer) MakeParserAndTokenizedProgram() {
 				if typeDefined != declarationType(DUMMY) {
 					iz.addTokenizedDeclaration(typeDefined, line, IsPrivate)
 				} else {
-					iz.Throw("init/type/form", &tok)
+					iz.Throw("init/type/defined", &tok)
 				}
 			default:
 				panic("Unhandled section type.")
@@ -674,7 +674,7 @@ func (iz *initializer) initializeExternals() {
 		// Otherwise we need to start up the service, add it to the hub, and then declare it as external.
 		newServiceCp, e := StartCompilerFromFilepath(path, iz.cp.Vm.Database, iz.Common.HubCompilers)
 		if e != nil { // Then we couldn't open the file.
-			iz.Throw("init/external/file", declaration.GetToken(), e)
+			iz.Throw("init/external/file", declaration.GetToken(), path, e.Error())
 		}
 		if len(newServiceCp.P.Common.Errors) > 0 {
 			newServiceCp.P.Common.IsBroken = true
@@ -936,7 +936,7 @@ func (iz *initializer) createClones() {
 					iz.Throw("init/request/map", &usingOrEof, op)
 				}
 			case values.PAIR:
-				iz.Throw("init/request/pair", &usingOrEof, op)
+				iz.Throw("init/request/pair", &usingOrEof)
 			case values.SET:
 				switch op {
 				case "+":
@@ -1790,8 +1790,8 @@ func (iz *initializer) CompileEverything() [][]labeledParsedCodeChunk {
 								iz.p.Throw("init/depend/cmd", dec.chunk.GetToken())
 								return nil
 							}
-							if rhsDec.decType == variableDeclaration {
-								iz.p.Throw("init/depend/const/var", dec.chunk.GetToken())
+							if rhsDec.decType == variableDeclaration && dec.decType != variableDeclaration{
+								iz.p.Throw("init/depend/var", dec.chunk.GetToken())
 								return nil
 							}
 						}
@@ -1837,12 +1837,12 @@ func (iz *initializer) CompileEverything() [][]labeledParsedCodeChunk {
 			decType := namesToDeclarations[svName][0].decType
 			decNumber := namesToDeclarations[svName][0].decNumber
 			if len(rhs) > 0 {
-				iz.p.Throw("init/service/depends", tok)
+				iz.p.Throw("init/service/depends", tok, svName)
 				return nil
 			}
 			iz.compileGlobalConstantOrVariable(decType, decNumber)
 			if svData.T != iz.cp.Vm.Mem[iz.cp.That()].T {
-				iz.p.Throw("init/service/type", tok)
+				iz.p.Throw("init/service/type", tok, svName, iz.cp.GetTypeNameFromNumber(svData.T))
 				return nil
 			}
 			delete(graph, svName)