Try to lex identifiers and parens

Sibil.xcodeproj/project.pbxproj

@@ -0,0 +1,266 @@
+// !$*UTF8*$!
+{
+	archiveVersion = 1;
+	classes = {
+	};
+	objectVersion = 46;
+	objects = {
+
+/* Begin PBXBuildFile section */
+		C0496EB51E04533D0000E33E /* main.swift in Sources */ = {isa = PBXBuildFile; fileRef = C0496EB41E04533D0000E33E /* main.swift */; };
+		C0496EBC1E04534F0000E33E /* Lexer.swift in Sources */ = {isa = PBXBuildFile; fileRef = C0496EBB1E04534F0000E33E /* Lexer.swift */; };
+		C0C60EC11E084631004C1559 /* Characters.swift in Sources */ = {isa = PBXBuildFile; fileRef = C0C60EC01E084631004C1559 /* Characters.swift */; };
+/* End PBXBuildFile section */
+
+/* Begin PBXCopyFilesBuildPhase section */
+		C0496EAF1E04533D0000E33E /* CopyFiles */ = {
+			isa = PBXCopyFilesBuildPhase;
+			buildActionMask = 2147483647;
+			dstPath = /usr/share/man/man1/;
+			dstSubfolderSpec = 0;
+			files = (
+			);
+			runOnlyForDeploymentPostprocessing = 1;
+		};
+/* End PBXCopyFilesBuildPhase section */
+
+/* Begin PBXFileReference section */
+		C0496EB11E04533D0000E33E /* Sibil */ = {isa = PBXFileReference; explicitFileType = "compiled.mach-o.executable"; includeInIndex = 0; path = Sibil; sourceTree = BUILT_PRODUCTS_DIR; };
+		C0496EB41E04533D0000E33E /* main.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = main.swift; sourceTree = "<group>"; };
+		C0496EBB1E04534F0000E33E /* Lexer.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = Lexer.swift; sourceTree = "<group>"; };
+		C0C60EC01E084631004C1559 /* Characters.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = Characters.swift; sourceTree = "<group>"; };
+/* End PBXFileReference section */
+
+/* Begin PBXFrameworksBuildPhase section */
+		C0496EAE1E04533D0000E33E /* Frameworks */ = {
+			isa = PBXFrameworksBuildPhase;
+			buildActionMask = 2147483647;
+			files = (
+			);
+			runOnlyForDeploymentPostprocessing = 0;
+		};
+/* End PBXFrameworksBuildPhase section */
+
+/* Begin PBXGroup section */
+		C0496EA81E04533D0000E33E = {
+			isa = PBXGroup;
+			children = (
+				C0496EB31E04533D0000E33E /* Sibil */,
+				C0496EB21E04533D0000E33E /* Products */,
+			);
+			sourceTree = "<group>";
+		};
+		C0496EB21E04533D0000E33E /* Products */ = {
+			isa = PBXGroup;
+			children = (
+				C0496EB11E04533D0000E33E /* Sibil */,
+			);
+			name = Products;
+			sourceTree = "<group>";
+		};
+		C0496EB31E04533D0000E33E /* Sibil */ = {
+			isa = PBXGroup;
+			children = (
+				C0496EB41E04533D0000E33E /* main.swift */,
+				C0496EBB1E04534F0000E33E /* Lexer.swift */,
+				C0C60EC01E084631004C1559 /* Characters.swift */,
+			);
+			path = Sibil;
+			sourceTree = "<group>";
+		};
+/* End PBXGroup section */
+
+/* Begin PBXNativeTarget section */
+		C0496EB01E04533D0000E33E /* Sibil */ = {
+			isa = PBXNativeTarget;
+			buildConfigurationList = C0496EB81E04533D0000E33E /* Build configuration list for PBXNativeTarget "Sibil" */;
+			buildPhases = (
+				C0496EAD1E04533D0000E33E /* Sources */,
+				C0496EAE1E04533D0000E33E /* Frameworks */,
+				C0496EAF1E04533D0000E33E /* CopyFiles */,
+			);
+			buildRules = (
+			);
+			dependencies = (
+			);
+			name = Sibil;
+			productName = Sibil;
+			productReference = C0496EB11E04533D0000E33E /* Sibil */;
+			productType = "com.apple.product-type.tool";
+		};
+/* End PBXNativeTarget section */
+
+/* Begin PBXProject section */
+		C0496EA91E04533D0000E33E /* Project object */ = {
+			isa = PBXProject;
+			attributes = {
+				LastSwiftUpdateCheck = 0810;
+				LastUpgradeCheck = 0810;
+				ORGANIZATIONNAME = "Eryn Wells";
+				TargetAttributes = {
+					C0496EB01E04533D0000E33E = {
+						CreatedOnToolsVersion = 8.1;
+						ProvisioningStyle = Automatic;
+					};
+				};
+			};
+			buildConfigurationList = C0496EAC1E04533D0000E33E /* Build configuration list for PBXProject "Sibil" */;
+			compatibilityVersion = "Xcode 3.2";
+			developmentRegion = English;
+			hasScannedForEncodings = 0;
+			knownRegions = (
+				en,
+			);
+			mainGroup = C0496EA81E04533D0000E33E;
+			productRefGroup = C0496EB21E04533D0000E33E /* Products */;
+			projectDirPath = "";
+			projectRoot = "";
+			targets = (
+				C0496EB01E04533D0000E33E /* Sibil */,
+			);
+		};
+/* End PBXProject section */
+
+/* Begin PBXSourcesBuildPhase section */
+		C0496EAD1E04533D0000E33E /* Sources */ = {
+			isa = PBXSourcesBuildPhase;
+			buildActionMask = 2147483647;
+			files = (
+				C0496EBC1E04534F0000E33E /* Lexer.swift in Sources */,
+				C0C60EC11E084631004C1559 /* Characters.swift in Sources */,
+				C0496EB51E04533D0000E33E /* main.swift in Sources */,
+			);
+			runOnlyForDeploymentPostprocessing = 0;
+		};
+/* End PBXSourcesBuildPhase section */
+
+/* Begin XCBuildConfiguration section */
+		C0496EB61E04533D0000E33E /* Debug */ = {
+			isa = XCBuildConfiguration;
+			buildSettings = {
+				ALWAYS_SEARCH_USER_PATHS = NO;
+				CLANG_ANALYZER_NONNULL = YES;
+				CLANG_CXX_LANGUAGE_STANDARD = "gnu++0x";
+				CLANG_CXX_LIBRARY = "libc++";
+				CLANG_ENABLE_MODULES = YES;
+				CLANG_ENABLE_OBJC_ARC = YES;
+				CLANG_WARN_BOOL_CONVERSION = YES;
+				CLANG_WARN_CONSTANT_CONVERSION = YES;
+				CLANG_WARN_DIRECT_OBJC_ISA_USAGE = YES_ERROR;
+				CLANG_WARN_DOCUMENTATION_COMMENTS = YES;
+				CLANG_WARN_EMPTY_BODY = YES;
+				CLANG_WARN_ENUM_CONVERSION = YES;
+				CLANG_WARN_INFINITE_RECURSION = YES;
+				CLANG_WARN_INT_CONVERSION = YES;
+				CLANG_WARN_OBJC_ROOT_CLASS = YES_ERROR;
+				CLANG_WARN_SUSPICIOUS_MOVES = YES;
+				CLANG_WARN_UNREACHABLE_CODE = YES;
+				CLANG_WARN__DUPLICATE_METHOD_MATCH = YES;
+				CODE_SIGN_IDENTITY = "-";
+				COPY_PHASE_STRIP = NO;
+				DEBUG_INFORMATION_FORMAT = dwarf;
+				ENABLE_STRICT_OBJC_MSGSEND = YES;
+				ENABLE_TESTABILITY = YES;
+				GCC_C_LANGUAGE_STANDARD = gnu99;
+				GCC_DYNAMIC_NO_PIC = NO;
+				GCC_NO_COMMON_BLOCKS = YES;
+				GCC_OPTIMIZATION_LEVEL = 0;
+				GCC_PREPROCESSOR_DEFINITIONS = (
+					"DEBUG=1",
+					"$(inherited)",
+				);
+				GCC_WARN_64_TO_32_BIT_CONVERSION = YES;
+				GCC_WARN_ABOUT_RETURN_TYPE = YES_ERROR;
+				GCC_WARN_UNDECLARED_SELECTOR = YES;
+				GCC_WARN_UNINITIALIZED_AUTOS = YES_AGGRESSIVE;
+				GCC_WARN_UNUSED_FUNCTION = YES;
+				GCC_WARN_UNUSED_VARIABLE = YES;
+				MACOSX_DEPLOYMENT_TARGET = 10.12;
+				MTL_ENABLE_DEBUG_INFO = YES;
+				ONLY_ACTIVE_ARCH = YES;
+				SDKROOT = macosx;
+				SWIFT_OPTIMIZATION_LEVEL = "-Onone";
+			};
+			name = Debug;
+		};
+		C0496EB71E04533D0000E33E /* Release */ = {
+			isa = XCBuildConfiguration;
+			buildSettings = {
+				ALWAYS_SEARCH_USER_PATHS = NO;
+				CLANG_ANALYZER_NONNULL = YES;
+				CLANG_CXX_LANGUAGE_STANDARD = "gnu++0x";
+				CLANG_CXX_LIBRARY = "libc++";
+				CLANG_ENABLE_MODULES = YES;
+				CLANG_ENABLE_OBJC_ARC = YES;
+				CLANG_WARN_BOOL_CONVERSION = YES;
+				CLANG_WARN_CONSTANT_CONVERSION = YES;
+				CLANG_WARN_DIRECT_OBJC_ISA_USAGE = YES_ERROR;
+				CLANG_WARN_DOCUMENTATION_COMMENTS = YES;
+				CLANG_WARN_EMPTY_BODY = YES;
+				CLANG_WARN_ENUM_CONVERSION = YES;
+				CLANG_WARN_INFINITE_RECURSION = YES;
+				CLANG_WARN_INT_CONVERSION = YES;
+				CLANG_WARN_OBJC_ROOT_CLASS = YES_ERROR;
+				CLANG_WARN_SUSPICIOUS_MOVES = YES;
+				CLANG_WARN_UNREACHABLE_CODE = YES;
+				CLANG_WARN__DUPLICATE_METHOD_MATCH = YES;
+				CODE_SIGN_IDENTITY = "-";
+				COPY_PHASE_STRIP = NO;
+				DEBUG_INFORMATION_FORMAT = "dwarf-with-dsym";
+				ENABLE_NS_ASSERTIONS = NO;
+				ENABLE_STRICT_OBJC_MSGSEND = YES;
+				GCC_C_LANGUAGE_STANDARD = gnu99;
+				GCC_NO_COMMON_BLOCKS = YES;
+				GCC_WARN_64_TO_32_BIT_CONVERSION = YES;
+				GCC_WARN_ABOUT_RETURN_TYPE = YES_ERROR;
+				GCC_WARN_UNDECLARED_SELECTOR = YES;
+				GCC_WARN_UNINITIALIZED_AUTOS = YES_AGGRESSIVE;
+				GCC_WARN_UNUSED_FUNCTION = YES;
+				GCC_WARN_UNUSED_VARIABLE = YES;
+				MACOSX_DEPLOYMENT_TARGET = 10.12;
+				MTL_ENABLE_DEBUG_INFO = NO;
+				SDKROOT = macosx;
+			};
+			name = Release;
+		};
+		C0496EB91E04533D0000E33E /* Debug */ = {
+			isa = XCBuildConfiguration;
+			buildSettings = {
+				PRODUCT_NAME = "$(TARGET_NAME)";
+				SWIFT_VERSION = 3.0;
+			};
+			name = Debug;
+		};
+		C0496EBA1E04533D0000E33E /* Release */ = {
+			isa = XCBuildConfiguration;
+			buildSettings = {
+				PRODUCT_NAME = "$(TARGET_NAME)";
+				SWIFT_VERSION = 3.0;
+			};
+			name = Release;
+		};
+/* End XCBuildConfiguration section */
+
+/* Begin XCConfigurationList section */
+		C0496EAC1E04533D0000E33E /* Build configuration list for PBXProject "Sibil" */ = {
+			isa = XCConfigurationList;
+			buildConfigurations = (
+				C0496EB61E04533D0000E33E /* Debug */,
+				C0496EB71E04533D0000E33E /* Release */,
+			);
+			defaultConfigurationIsVisible = 0;
+			defaultConfigurationName = Release;
+		};
+		C0496EB81E04533D0000E33E /* Build configuration list for PBXNativeTarget "Sibil" */ = {
+			isa = XCConfigurationList;
+			buildConfigurations = (
+				C0496EB91E04533D0000E33E /* Debug */,
+				C0496EBA1E04533D0000E33E /* Release */,
+			);
+			defaultConfigurationIsVisible = 0;
+			defaultConfigurationName = Release;
+		};
+/* End XCConfigurationList section */
+	};
+	rootObject = C0496EA91E04533D0000E33E /* Project object */;
+}

Sibil.xcodeproj/project.xcworkspace/contents.xcworkspacedata

@@ -0,0 +1,7 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<Workspace
+   version = "1.0">
+   <FileRef
+      location = "self:Sibil.xcodeproj">
+   </FileRef>
+</Workspace>

Sibil/Characters.swift

@@ -0,0 +1,60 @@
+//
+//  Characters.swift
+//  Sibil
+//
+//  Created by Eryn Wells on 12/19/16.
+//  Copyright © 2016 Eryn Wells. All rights reserved.
+//
+
+import Foundation
+
+
+extension CharacterSet {
+    static let asciiLetters: CharacterSet = {
+        return CharacterSet(charactersIn: "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ")
+    }()
+
+    static let asciiDigits: CharacterSet = {
+        return CharacterSet(charactersIn: "1234567890")
+    }()
+
+    static let identifierInitials: CharacterSet = {
+        let letters = CharacterSet.asciiLetters
+        let extras = CharacterSet(charactersIn: "!$%&*/:<=>?~_^")
+        let initials = letters.union(extras)
+        return initials
+    }()
+
+    static let identifierSubsequents: CharacterSet = {
+        let initials = CharacterSet.identifierInitials
+        let digits = CharacterSet.asciiDigits
+        let extras = CharacterSet(charactersIn: ".+-")
+        let subsequents = initials.union(digits).union(extras)
+        return subsequents
+    }()
+
+    func contains(_ c: Character) -> Bool {
+        let cSet = CharacterSet(charactersIn: String(c))
+        let containsC = isSuperset(of: cSet)
+        return containsC
+    }
+}
+
+
+extension Character {
+    var isLeftParen: Bool {
+        return self == "("
+    }
+
+    var isRightParen: Bool {
+        return self == ")"
+    }
+
+    var isIdentifierInitial: Bool {
+        return CharacterSet.identifierInitials.contains(self)
+    }
+
+    var isIdentifierSubsequent: Bool {
+        return CharacterSet.identifierSubsequents.contains(self)
+    }
+}

Sibil/Lexer.swift

@@ -0,0 +1,117 @@
+//
+//  Lexer.swift
+//  Sibil
+//
+//  Created by Eryn Wells on 12/16/16.
+//  Copyright © 2016 Eryn Wells. All rights reserved.
+//
+
+import Foundation
+
+
+struct Token: CustomDebugStringConvertible {
+    enum Kind {
+        case LeftParen
+        case RightParen
+        case Identifier
+    }
+    
+    let kind: Kind
+    let value: String
+
+    // MARK: CustomDebugStringConvertible
+
+    var debugDescription: String {
+        return "Token(kind: .\(kind), value: \"\(value)\")"
+    }
+}
+
+
+class Lexer {
+    let input: String
+
+    var index: String.Index
+
+    init(input: String) {
+        self.input = input
+        self.index = input.startIndex
+    }
+}
+
+extension Lexer: Sequence, IteratorProtocol {
+    typealias Element = Token
+
+    private enum State {
+        case Initial
+        case Identifier
+        case Emit
+    }
+
+    func makeIterator() -> Lexer {
+        return self
+    }
+
+    func next() -> Token? {
+        guard index != input.endIndex else {
+            return nil
+        }
+
+        var state = State.Initial
+        var token: Token?
+        var forward = index
+
+        let toState = { (nextState: State) in
+            state = nextState
+        }
+
+        let retract = {
+            forward = self.input.index(before: forward)
+        }
+
+        let advance = {
+            forward = self.input.index(after: forward)
+        }
+
+        let emit = { (kind: Token.Kind) in
+            let valueRange = Range(uncheckedBounds: (lower: self.index, upper: forward))
+            let value = self.input.substring(with: valueRange)
+            token = Token(kind: kind, value: value)
+            toState(.Emit)
+        }
+
+        while state != .Emit {
+            let c = input[forward]
+            print("processing '\(c)' in \(state)")
+            switch state {
+            case .Initial:
+                if c.isLeftParen {
+                    emit(.LeftParen)
+                }
+                else if c.isRightParen {
+                    emit(.RightParen)
+                }
+                else if c.isIdentifierInitial {
+                    advance()
+                    toState(.Identifier)
+                }
+            case .Identifier:
+                if c.isIdentifierSubsequent {
+                    advance()
+                }
+                else {
+                    retract()
+                    emit(.Identifier)
+                }
+                break
+            case .Emit:
+                // Nothing to do for this state
+                break
+            }
+        }
+
+        // Set up for the next token.
+        index = input.index(after: forward)
+
+        return token
+    }
+}

Sibil/main.swift

@@ -0,0 +1,15 @@
+//
+//  main.swift
+//  Sibil
+//
+//  Created by Eryn Wells on 12/16/16.
+//  Copyright © 2016 Eryn Wells. All rights reserved.
+//
+
+import Foundation
+
+let l = Lexer(input: "((abc))")
+for t in l {
+    print(t)
+}
+