Merge pull request #17 from igorkulman/builtin-functions

Builtin functions

Author: igorkulman

.gitignore

@@ -65,3 +65,4 @@ fastlane/report.xml
 fastlane/Preview.html
 fastlane/screenshots
 fastlane/test_output
+/Examples/SPI

Examples/factorial.pas

@@ -0,0 +1,20 @@
+program Main;
+var input, result: integer;
+
+function Factorial(number: Integer): Integer;
+begin
+if (number > 1) then
+    Factorial := number * Factorial(number-1)
+else
+    Factorial := 1
+end;
+
+begin { Main }
+writeln('Factorial');
+writeln('');
+writeln('Enter number and press Enter');
+read(input);
+result := Factorial(input);
+writeln('');
+writeln(input,'! = ', result)
+end.  { Main }

Examples/helloworld.pas

@@ -0,0 +1,4 @@
+Program HelloWorld;
+Begin
+	Writeln('Hello World');
+End.

Examples/name.pas

@@ -0,0 +1,12 @@
+Program Name;
+Var name, surname: String;
+     
+Begin
+	write('Enter your name:');
+	read(name);
+	write('Enter your surname:');
+	read(surname);
+	writeln();{new line}
+	writeln();{new line}
+	writeln('Your full name is: ',name,' ',surname);
+End.

Examples/numbers.pas

@@ -0,0 +1,13 @@
+Program Numbers;
+Var       
+    Num1, Num2, Sum : Integer;
+
+Begin {no semicolon}
+	Write('Input number 1:'); 
+	Read(Num1);
+	Write('Input number 2:');
+	Read(Num2);
+	Sum := Num1 + Num2; {addition} 
+	Writeln();
+	Writeln(Num1,'+', Num2,'=', Sum);
+End.  

Images/cli.gif

@@ -7,3 +7,4 @@ disabled_rules:
     - function_body_length
     - type_body_length
     - file_length
+    - large_tuple

PascalInterpreter/.swiftlint.yml

@@ -30,6 +30,7 @@
 		F300A0F11FDDB77000E5894D /* InterpreterTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = F300A0EC1FDDB77000E5894D /* InterpreterTests.swift */; };
 		F300A0F21FDDB77000E5894D /* SemanticAnalyzerTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = F300A0ED1FDDB77000E5894D /* SemanticAnalyzerTests.swift */; };
 		F34109A81FE2683900271A57 /* Visitor.swift in Sources */ = {isa = PBXBuildFile; fileRef = F34109A71FE2683900271A57 /* Visitor.swift */; };
+		F3D90E131FE6A0C600FA79B3 /* Interpreter+Standard.swift in Sources */ = {isa = PBXBuildFile; fileRef = F3D90E121FE6A0C600FA79B3 /* Interpreter+Standard.swift */; };
 		F3EF28D01FE12EBF001F36AB /* Frame.swift in Sources */ = {isa = PBXBuildFile; fileRef = F3EF28CF1FE12EBF001F36AB /* Frame.swift */; };
 		F3EF28D21FE12F4D001F36AB /* Stack.swift in Sources */ = {isa = PBXBuildFile; fileRef = F3EF28D11FE12F4D001F36AB /* Stack.swift */; };
 /* End PBXBuildFile section */
@@ -71,6 +72,7 @@
 		F300A0EC1FDDB77000E5894D /* InterpreterTests.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = InterpreterTests.swift; sourceTree = "<group>"; };
 		F300A0ED1FDDB77000E5894D /* SemanticAnalyzerTests.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = SemanticAnalyzerTests.swift; sourceTree = "<group>"; };
 		F34109A71FE2683900271A57 /* Visitor.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = Visitor.swift; sourceTree = "<group>"; };
+		F3D90E121FE6A0C600FA79B3 /* Interpreter+Standard.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "Interpreter+Standard.swift"; sourceTree = "<group>"; };
 		F3EF28CF1FE12EBF001F36AB /* Frame.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = Frame.swift; sourceTree = "<group>"; };
 		F3EF28D11FE12F4D001F36AB /* Stack.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = Stack.swift; sourceTree = "<group>"; };
 /* End PBXFileReference section */
@@ -142,8 +144,9 @@
 				F300A0C51FDDB6BE00E5894D /* Arithmetics.swift */,
 				F3EF28CF1FE12EBF001F36AB /* Frame.swift */,
 				F300A0C61FDDB6BE00E5894D /* Interpreter.swift */,
-				F300A0C41FDDB6BD00E5894D /* Value.swift */,
+				F3D90E121FE6A0C600FA79B3 /* Interpreter+Standard.swift */,
 				F3EF28D11FE12F4D001F36AB /* Stack.swift */,
+				F300A0C41FDDB6BD00E5894D /* Value.swift */,
 			);
 			path = Interpreter;
 			sourceTree = "<group>";
@@ -348,6 +351,7 @@
 				F300A0C91FDDB6BE00E5894D /* Interpreter.swift in Sources */,
 				F3EF28D01FE12EBF001F36AB /* Frame.swift in Sources */,
 				F300A0C71FDDB6BE00E5894D /* Value.swift in Sources */,
+				F3D90E131FE6A0C600FA79B3 /* Interpreter+Standard.swift in Sources */,
 				F3EF28D21FE12F4D001F36AB /* Stack.swift in Sources */,
 				F300A0E71FDDB74800E5894D /* SymbolTable.swift in Sources */,
 				F300A0D81FDDB6F400E5894D /* AST+Extensions.swift in Sources */,

PascalInterpreter/PascalInterpreter.xcodeproj/project.pbxproj

@@ -12,9 +12,10 @@ class Frame {
     var integerMemory: [String: Int] = [:]
     var realMemory: [String: Double] = [:]
     var booleanMemory: [String: Bool] = [:]
+    var stringMemory: [String: String] = [:]
     let scope: ScopedSymbolTable
     let previousFrame: Frame?
-    var returnValue: Value?
+    var returnValue: Value = .none
 
     init(scope: ScopedSymbolTable, previousFrame: Frame?) {
         self.scope = scope
@@ -43,8 +44,8 @@ class Frame {
                     case .real:
                         fatalError("Cannot assign Real value to Int variable \(variable)")
                     }
-                case .boolean:
-                    fatalError("Cannot assign Boolean value to Int variable \(variable)")
+                default:
+                    fatalError("Cannot assign \(value) to Int variable \(variable)")
                 }
             case .real:
                 switch value {
@@ -55,8 +56,8 @@ class Frame {
                     case let .real(value):
                         realMemory[variable] = value
                     }
-                case .boolean:
-                    fatalError("Cannot assign Boolean value to Real variable \(variable)")
+                default:
+                    fatalError("Cannot assign \(value) to Real variable \(variable)")
                 }
             case .boolean:
                 switch value {
@@ -65,6 +66,13 @@ class Frame {
                 default:
                     fatalError("Cannot assign \(value) value to Boolean variable \(variable)")
                 }
+            case .string:
+                switch value {
+                case let .string(string):
+                    stringMemory[variable] = string
+                default:
+                    fatalError("Cannot assign \(value) value to String variable \(variable)")
+                }
             }
             return
         }
@@ -86,6 +94,8 @@ class Frame {
                 return .number(.real(realMemory[variable]!))
             case .boolean:
                 return .boolean(booleanMemory[variable]!)
+            case .string:
+                return .string(stringMemory[variable]!)
             }
         }
 

PascalInterpreter/PascalInterpreter/Interpreter/Frame.swift

@@ -0,0 +1,84 @@
+//
+//  Interpreter+Standard.swift
+//  PascalInterpreter
+//
+//  Created by Igor Kulman on 17/12/2017.
+//  Copyright © 2017 Igor Kulman. All rights reserved.
+//
+
+import Foundation
+
+extension Interpreter {
+    func callBuiltInProcedure(procedure: String, params: [AST], frame: Frame) -> Value {
+        switch procedure.uppercased() {
+        case "WRITE":
+            write(params: params, newLine: false)
+            return .none
+        case "WRITELN":
+            write(params: params, newLine: true)
+            return .none
+        case "READ":
+            read(params: params, frame: frame)
+            return .none
+        case "READLN":
+            read(params: params, frame: frame)
+            return .none
+        default:
+            fatalError("Implement built in procedure \(procedure)")
+        }
+    }
+
+    private func write(params: [AST], newLine: Bool) {
+        var s = ""
+        for param in params {
+            let value = eval(node: param)
+            switch value {
+            case let .boolean(value):
+                s += value ? "TRUE" : "FALSE"
+            case let .number(number):
+                switch number {
+                case let .integer(value):
+                    s += String(value)
+                case let .real(value):
+                    s += String(value)
+                }
+            case let .string(value):
+                s += value
+            case .none:
+                fatalError("Cannot use WRITE with expression without a value")
+            }
+        }
+        if newLine {
+            print(s)
+        } else {
+            print(s, terminator: "")
+        }
+    }
+
+    private func read(params: [AST], frame: Frame) {
+        guard let line = readLine() else {
+            fatalError("Empty input")
+        }
+
+        let parts = line.components(separatedBy: CharacterSet.whitespaces)
+        for i in 0 ... params.count - 1 {
+            let param = params[i]
+            guard let variable = param as? Variable else {
+                fatalError("READ parameter must be a variable")
+            }
+            guard let symbol = frame.scope.lookup(variable.name), let variableSymbol = symbol as? VariableSymbol, let type = variableSymbol.type as? BuiltInTypeSymbol else {
+                fatalError("Symbol(variable) not found '\(variable.name)'")
+            }
+            switch type {
+            case .integer:
+                frame.set(variable: variable.name, value: .number(.integer(Int(parts[i])!)))
+            case .real:
+                frame.set(variable: variable.name, value: .number(.real(Double(parts[i])!)))
+            case .boolean:
+                frame.set(variable: variable.name, value: .boolean(Bool(parts[i])!))
+            case .string:
+                frame.set(variable: variable.name, value: .string((parts[i])))
+            }
+        }
+    }
+}