- updated to Swift 5 (untested)

Author: martinpi

Common/Analyzer/CyclicReferenceIdentifier.swift

@@ -281,7 +281,7 @@ fileprivate struct JohnsonCircuitFindingAlgorithm {
             items.append(item)
         }
         mutating func remove(item: Int) {
-            if let i = items.index(where: {$0 == item}) {
+			if let i = items.firstIndex(where: {$0 == item}) {
                 items.remove(at: i)
             }
         }

Common/Analyzer/RulesetAnalyser.swift

@@ -37,5 +37,4 @@ extension Tracery {
         }
         analyzers.forEach { $0.end() }
     }
-    
 }

Common/Kalk/Kalk.Interpreter.swift

@@ -74,12 +74,11 @@ public class KalkInterpreter {
 				(Double(arc4random()) / Double(UINT32_MAX)) * (value2.getDouble()!-value.getDouble()!))
 		}
 	}
-	
+
 	public static func interpret(_ string: String) -> String {
 		let lexer = KalkLexer(input: string)
 		let tokens = lexer.tokenize()
 		let parser = KalkParser(tokens: tokens)
-		registerBuiltins()
 		var expandedString: String = ""
 		do {
 			let nodes = try parser.parse()

Common/Kalk/Kalk.Regex.swift

@@ -10,7 +10,7 @@ import Foundation
 
 var expressions = [String: NSRegularExpression]()
 public extension String {
-    public func match(regex: String) -> String? {
+	func match(regex: String) -> String? {
         let expression: NSRegularExpression
         if let exists = expressions[regex] {
             expression = exists

Common/Lexer.swift

@@ -45,7 +45,9 @@ enum Token : CustomStringConvertible {
     static let RIGHT_ROUND_BRACKET = Token.op(")")
     static let LEFT_CURLY_BRACKET = Token.op("{")
     static let RIGHT_CURLY_BRACKET = Token.op("}")
-    
+
+	static let ASSIGN = Token.op("=")
+
     static let EQUAL_TO = Token.op("==")
     static let NOT_EQUAL_TO = Token.op("!=")
 
@@ -82,7 +84,7 @@ func ==(lhs: Token, rhs: Token) -> Bool {
 extension Character {
     var isReserved: Bool {
         switch self {
-        case "[","]",":","#",",","(",")",".","{","}": return true
+        case "[","]",":","#",",","(",")",".","{","}","=": return true
         default: return false
         }
     }

Common/Modifiers.swift

@@ -168,6 +168,7 @@ public class StandardModifiers {
 
 //		t.add(modifier: "k", transform: KalkInterpreter.interpret)
 
+		KalkInterpreter.registerBuiltins()
 		t.add(method: "k") { input, args in
 			return input + KalkInterpreter.interpret(args[0])
 		}

Common/Parser.Gen2.swift

@@ -309,6 +309,17 @@ extension Parser {
             guard let c = currentToken, c == token else { return }
             advance()
         }
+		
+		func parseFormula() throws -> ParserNode {
+
+			// calculations
+			// [=3+2]
+			// [=sin(3.2)]
+			let formula = try parseText("expected formula")
+//			nodes.append(ParserNode.kalk(name))
+//			try parseAny([.HASH, .RIGHT_CURLY_BRACKET], "closing # or } not found for rule '\(name)'")
+			return ParserNode.kalk(formula)
+		}
 
         // a fragment is the most basic block in tracery
         // a fragement can contain multiple parser nodes though
@@ -323,6 +334,8 @@ extension Parser {
             case Token.LEFT_SQUARE_BRACKET:
                 guard let next = nextToken else { return nil }
                 switch next {
+				case Token.ASSIGN:
+					nodes.append(try parseFormula())
                 case Token.KEYWORD_IF:
                     nodes.append(contentsOf: try parseIfBlock())
                 case Token.KEYWORD_WHILE:

Common/Parser.swift

@@ -64,6 +64,7 @@ enum ParserNode : CustomStringConvertible {
 
     case text(String)
     case rule(name:String, mods:[Modifier])
+	case kalk(String)
     case any(values:[ValueCandidate], selector:RuleCandidateSelector, mods:[Modifier])
     case tag(name:String, values:[ValueCandidate])
     case weight(value: Int)
@@ -98,6 +99,9 @@ enum ParserNode : CustomStringConvertible {
             }
             return "RULE_\(name)"
 
+		case let .kalk(formula):
+			return "KALK_\(formula)"
+			
         case let .createRule(name, values):
             if values.count == 1 { return "NEW_RULE(\(name)=\(values[0]))" }
             return "+RULE_\(name)=\(values)"

Common/Tracery.Eval.swift

@@ -10,7 +10,7 @@ import Foundation
 
 
 extension Tracery {
-    
+	
     // transforms input text to expanded text
     // based on the rule set, run time tags, and modifiers
     func eval(_ text: String) throws -> String {
@@ -29,7 +29,9 @@ extension Tracery {
     }
 
     func eval(_ nodes: [ParserNode]) throws -> String {
-        
+		
+		var choices = 1
+		
         // the execution stack
         // var stack = [ExecutionContext]()
         contextStack.reset()
@@ -98,15 +100,7 @@ extension Tracery {
                 }
             }
 
-//            do {
-//                let i = depth
-//                let context = stack[i]
-//                trace("\(i) \(context)")
-//            }
-            
-            
-            // have we have finished processing
-            // the stack?
+            // have we finished processing the stack?
             if contextStack.executionComplete {
                 break
             }
@@ -130,7 +124,10 @@ extension Tracery {
                 trace("📘 text '\(text)'")
                 // commit result to context
                 contextStack.contexts[top].result.append(text)
-                
+
+			case let .kalk(formula):
+				contextStack.contexts[top].result = KalkInterpreter.interpret(formula)
+				
             case let .evaluateArg(nodes):
                 // special node that evaluates
                 // child nodes and adds result
@@ -145,7 +142,8 @@ extension Tracery {
                 try applyMods(nodes: choice.nodes, mods: mods)
                 // try pushContext(choice.nodes, affectsEvaluationLevel: false)
                 trace("🎲 picked \(choice.nodes)")
-                
+				choices *= values.count
+
             case let .tag(name, values):
 
                 // push a context with
@@ -239,9 +237,7 @@ extension Tracery {
                         try pushContext(elseBlock, affectsEvaluationLevel: false)
                     }
                 }
-                
-                
-                
+				
             case let .runMod(name):
                 guard let mod = mods[name] else { break }
                 let context = contextStack.contexts[top]
@@ -281,12 +277,10 @@ extension Tracery {
 						return
 					}
 
-//                    guard let candidate = mapping.select() else {
-//                        state = .noExpansion(reason: "no candidates found")
-//                        return
-//                    }
                     state = .apply(mapping.candidates[index].value.nodes)
                     trace("📙 eval \(runTime ? "runtime" : "") \(node)")
+					
+					choices *= mapping.candidates.count
                 }
 
                 if name.isEmpty {
@@ -297,6 +291,7 @@ extension Tracery {
                     let value = mapping.candidates[i]
                     trace("📗 get tag[\(name)] --> \(value)")
                     state = .apply([.text(value)])
+					choices *= mapping.candidates.count
                 }
                 else if let object = objects[name] {
                     let value = "\(object)"
@@ -319,6 +314,8 @@ extension Tracery {
                 }
             }
         }
+		
+		trace("🧾 had \(choices) options to chose from")
 
         // finally pop the last
         // context and

Common/Tracery.Logging.swift

@@ -58,7 +58,7 @@ func error(_ message: @autoclosure () -> String) {
 }
 
 func trace(_ message: @autoclosure () -> String) {
-    Tracery.log(level: .verbose, message: message)
+	Tracery.log(level: .verbose, message: message())
 }