Merge pull request #47 from jakerockland/race-conditions-and-swift-4

Fix potential race conditions and finish update for Swift 4

Author: jakerockland

Sources/SwispFramework/Environment.swift

@@ -441,7 +441,7 @@ private struct Library {
         case let (val as Bool):
             return !val
         case let (val as NSNumber):
-            return !Bool(val)
+            return !Bool(truncating: val)
         case let (val as String):
             if let bool = Bool(val) {
                 return !bool
@@ -691,7 +691,7 @@ private struct Math {
         }
         switch (args[safe: 0], args[safe: 1]) {
         case let (val as Double, exp as Int):
-            return Foundation.ldexp(val, exp)
+            return Foundation.scalbn(val, exp)
         default:
             throw SwispError.SyntaxError(message: "invalid procedure input")
         }

Sources/SwispFramework/Interpreter.swift

@@ -52,7 +52,7 @@ public struct Interpreter {
         /// Calls the given procedure
         public func call(_ args: [Any]) throws -> Any? {
             var inner = Env(parms, args, outer: env)
-            return try Interpreter.eval(&body, with: &inner)
+            return try Interpreter.eval(body, with: &inner)
         }
 
     }
@@ -184,7 +184,7 @@ public struct Interpreter {
 
      - Returns: The evaluated statement
      */
-    static func eval(_ x: inout Any, with env: inout Env) throws -> Any? {
+    static func eval(_ x: Any, with env: inout Env) throws -> Any? {
         if let x = x as? Symbol { // variable reference
             guard let ref = env.find(x)?[x] else {
                 return x
@@ -210,25 +210,25 @@ public struct Interpreter {
                 }
                 return lis
             } else if x.first as? Symbol == "if" { // conditional
-                guard var test = x[safe: 1], let conseq = x[safe: 2], let alt = x[safe: 3] else {
+                guard let test = x[safe: 1], let conseq = x[safe: 2], let alt = x[safe: 3] else {
                     throw SwispError.SyntaxError(message: "invalid conditional statement")
                 }
-                guard let bool = try eval(&test, with: &env) as? Bool else {
+                guard let bool = try eval(test, with: &env) as? Bool else {
                     throw SwispError.SyntaxError(message: "invalid conditional statement")
                 }
-                var exp = bool ? conseq : alt
-                return try eval(&exp, with: &env)
+                let exp = bool ? conseq : alt
+                return try eval(exp, with: &env)
             } else if x.first as? Symbol == "define" { // definition
-                guard let `var` = x[safe: 1] as? Symbol, var exp = x[safe: 2] else {
+                guard let `var` = x[safe: 1] as? Symbol, let exp = x[safe: 2] else {
                     throw SwispError.SyntaxError(message: "invalid definition")
                 }
-                env[`var`] = try eval(&exp, with: &env)
+                env[`var`] = try eval(exp, with: &env)
                 return nil
             } else if x.first as? Symbol == "set!" { // assignment
-                guard let `var` = x[safe: 1] as? Symbol, var exp = x[safe: 2], let outer = env.find(`var`) else {
+                guard let `var` = x[safe: 1] as? Symbol, let exp = x[safe: 2], let outer = env.find(`var`) else {
                     throw SwispError.SyntaxError(message: "invalid assignment")
                 }
-                outer[`var`] = try eval(&exp, with: &env)
+                outer[`var`] = try eval(exp, with: &env)
                 return nil
             } else if x.first as? Symbol == "lambda" { // lambda
                 guard let parms = x[safe: 1] as? [Symbol], let body = x[safe: 2] as? [Any] else {
@@ -237,15 +237,15 @@ public struct Interpreter {
                 return Lambda(parms, body, env)
             } else { // procedure call
                 var args: [Any] = []
-                guard var exp = x[safe: 0] else {
+                guard let exp = x[safe: 0] else {
                     throw SwispError.SyntaxError(message: "invalid procedure called")
                 }
 
-                let proc = try eval(&exp, with: &env)
+                let proc = try eval(exp, with: &env)
 
                 for element in x.dropFirst() {
-                    var element = element
-                    guard let arg = try eval(&element, with: &env) else {
+                    let element = element
+                    guard let arg = try eval(element, with: &env) else {
                         throw SwispError.SyntaxError(message: "invalid procedure called")
                     }
                     args.append(arg)
@@ -287,8 +287,8 @@ public struct Interpreter {
             }
 
             do {
-                var parsed = try Interpreter.parse(input)
-                if var val = try Interpreter.eval(&parsed, with: &globalEnv) {
+                let parsed = try Interpreter.parse(input)
+                if var val = try Interpreter.eval(parsed, with: &globalEnv) {
                     print(Interpreter.schemeString(&val))
                 }
             } catch let error as SwispError {

Swisp.xcodeproj/project.pbxproj

@@ -48,9 +48,9 @@
 		OBJ_15 /* EnvironmentTests.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = EnvironmentTests.swift; sourceTree = "<group>"; };
 		OBJ_16 /* InterpreterTests.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = InterpreterTests.swift; sourceTree = "<group>"; };
 		OBJ_17 /* XCTestManifests.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = XCTestManifests.swift; sourceTree = "<group>"; };
-		OBJ_19 /* Swisp */ = {isa = PBXFileReference; lastKnownFileType = text; path = Swisp; sourceTree = BUILT_PRODUCTS_DIR; };
+		OBJ_19 /* Swisp */ = {isa = PBXFileReference; explicitFileType = "compiled.mach-o.executable"; path = Swisp; sourceTree = BUILT_PRODUCTS_DIR; };
 		OBJ_20 /* SwispFramework.framework */ = {isa = PBXFileReference; explicitFileType = wrapper.framework; path = SwispFramework.framework; sourceTree = BUILT_PRODUCTS_DIR; };
-		OBJ_21 /* SwispTests.xctest */ = {isa = PBXFileReference; lastKnownFileType = file; path = SwispTests.xctest; sourceTree = BUILT_PRODUCTS_DIR; };
+		OBJ_21 /* SwispTests.xctest */ = {isa = PBXFileReference; explicitFileType = wrapper.cfbundle; path = SwispTests.xctest; sourceTree = BUILT_PRODUCTS_DIR; };
 		OBJ_6 /* Package.swift */ = {isa = PBXFileReference; explicitFileType = sourcecode.swift; path = Package.swift; sourceTree = "<group>"; };
 		OBJ_9 /* main.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = main.swift; sourceTree = "<group>"; };
 /* End PBXFileReference section */
@@ -215,6 +215,17 @@
 			isa = PBXProject;
 			attributes = {
 				LastUpgradeCheck = 9999;
+				TargetAttributes = {
+					OBJ_22 = {
+						LastSwiftMigration = 1000;
+					};
+					OBJ_31 = {
+						LastSwiftMigration = 1000;
+					};
+					OBJ_39 = {
+						LastSwiftMigration = 1000;
+					};
+				};
 			};
 			buildConfigurationList = OBJ_2 /* Build configuration list for PBXProject "Swisp" */;
 			compatibilityVersion = "Xcode 3.2";
@@ -295,6 +306,8 @@
 				OTHER_SWIFT_FLAGS = "$(inherited)";
 				SWIFT_FORCE_DYNAMIC_LINK_STDLIB = YES;
 				SWIFT_FORCE_STATIC_LINK_STDLIB = NO;
+				SWIFT_SWIFT3_OBJC_INFERENCE = Default;
+				SWIFT_VERSION = 4.2;
 				TARGET_NAME = Swisp;
 			};
 			name = Debug;
@@ -313,6 +326,8 @@
 				OTHER_SWIFT_FLAGS = "$(inherited)";
 				SWIFT_FORCE_DYNAMIC_LINK_STDLIB = YES;
 				SWIFT_FORCE_STATIC_LINK_STDLIB = NO;
+				SWIFT_SWIFT3_OBJC_INFERENCE = Default;
+				SWIFT_VERSION = 4.2;
 				TARGET_NAME = Swisp;
 			};
 			name = Release;
@@ -355,6 +370,8 @@
 				PRODUCT_BUNDLE_IDENTIFIER = SwispFramework;
 				PRODUCT_MODULE_NAME = "$(TARGET_NAME:c99extidentifier)";
 				PRODUCT_NAME = "$(TARGET_NAME:c99extidentifier)";
+				SWIFT_SWIFT3_OBJC_INFERENCE = Default;
+				SWIFT_VERSION = 4.2;
 				TARGET_NAME = SwispFramework;
 			};
 			name = Debug;
@@ -375,6 +392,8 @@
 				PRODUCT_BUNDLE_IDENTIFIER = SwispFramework;
 				PRODUCT_MODULE_NAME = "$(TARGET_NAME:c99extidentifier)";
 				PRODUCT_NAME = "$(TARGET_NAME:c99extidentifier)";
+				SWIFT_SWIFT3_OBJC_INFERENCE = Default;
+				SWIFT_VERSION = 4.2;
 				TARGET_NAME = SwispFramework;
 			};
 			name = Release;
@@ -412,6 +431,8 @@
 				LD_RUNPATH_SEARCH_PATHS = "@loader_path/../Frameworks";
 				OTHER_LDFLAGS = "$(inherited)";
 				OTHER_SWIFT_FLAGS = "$(inherited)";
+				SWIFT_SWIFT3_OBJC_INFERENCE = Default;
+				SWIFT_VERSION = 4.2;
 				TARGET_NAME = SwispTests;
 			};
 			name = Debug;
@@ -429,6 +450,8 @@
 				LD_RUNPATH_SEARCH_PATHS = "@loader_path/../Frameworks";
 				OTHER_LDFLAGS = "$(inherited)";
 				OTHER_SWIFT_FLAGS = "$(inherited)";
+				SWIFT_SWIFT3_OBJC_INFERENCE = Default;
+				SWIFT_VERSION = 4.2;
 				TARGET_NAME = SwispTests;
 			};
 			name = Release;