language: add unary plus & minus, post increment & decrement operators, non-newline print builtin. fix block comments

ast/src/main/ast/pork.yml

@@ -181,6 +181,12 @@ types:
     - name: Negate
       values:
         token: "!"
+    - name: UnaryPlus
+      values:
+        token: "+"
+    - name: UnaryMinus
+      values:
+        token: "-"
   PrefixOperation:
     parent: Expression
     values:
@@ -188,6 +194,24 @@ types:
       type: PrefixOperator
     - name: expression
       type: Expression
+  SuffixOperator:
+    values:
+    - name: token
+      type: String
+    enums:
+    - name: Increment
+      values:
+        token: "++"
+    - name: Decrement
+      values:
+        token: "--"
+  SuffixOperation:
+    parent: Expression
+    values:
+    - name: op
+      type: SuffixOperator
+    - name: reference
+      type: SymbolReference
   StringLiteral:
     parent: Expression
     values:

ast/src/main/graph/types.dot

@@ -24,6 +24,8 @@ digraph A {
   type_Parentheses [shape=box,label="Parentheses"]
   type_PrefixOperator [shape=box,label="PrefixOperator"]
   type_PrefixOperation [shape=box,label="PrefixOperation"]
+  type_SuffixOperator [shape=box,label="SuffixOperator"]
+  type_SuffixOperation [shape=box,label="SuffixOperation"]
   type_StringLiteral [shape=box,label="StringLiteral"]
   type_SymbolReference [shape=box,label="SymbolReference"]
   type_While [shape=box,label="While"]
@@ -49,6 +51,7 @@ digraph A {
   type_Expression -> type_ListLiteral
   type_Expression -> type_Parentheses
   type_Expression -> type_PrefixOperation
+  type_Expression -> type_SuffixOperation
   type_Expression -> type_StringLiteral
   type_Expression -> type_SymbolReference
   type_Expression -> type_While
@@ -84,6 +87,8 @@ digraph A {
   type_Parentheses -> type_Expression [style=dotted]
   type_PrefixOperation -> type_PrefixOperator [style=dotted]
   type_PrefixOperation -> type_Expression [style=dotted]
+  type_SuffixOperation -> type_SuffixOperator [style=dotted]
+  type_SuffixOperation -> type_SymbolReference [style=dotted]
   type_SymbolReference -> type_Symbol [style=dotted]
   type_While -> type_Expression [style=dotted]
   type_While -> type_Block [style=dotted]

ast/src/main/kotlin/gay/pizza/pork/ast/NodeCoalescer.kt

@@ -59,6 +59,9 @@ class NodeCoalescer(val handler: (Node) -> Unit) : NodeVisitor<Unit> {
   override fun visitStringLiteral(node: StringLiteral): Unit =
     handle(node)
 
+  override fun visitSuffixOperation(node: SuffixOperation): Unit =
+    handle(node)
+
   override fun visitSymbol(node: Symbol): Unit =
     handle(node)
 

ast/src/main/kotlin/gay/pizza/pork/ast/NodeType.kt

@@ -25,6 +25,7 @@ enum class NodeType(val parent: NodeType? = null) {
   PrefixOperation(Expression),
   SetAssignment(Expression),
   StringLiteral(Expression),
+  SuffixOperation(Expression),
   Symbol(Node),
   SymbolReference(Expression),
   VarAssignment(Expression),

ast/src/main/kotlin/gay/pizza/pork/ast/NodeVisitor.kt

@@ -40,6 +40,8 @@ interface NodeVisitor<T> {
 
   fun visitStringLiteral(node: StringLiteral): T
 
+  fun visitSuffixOperation(node: SuffixOperation): T
+
   fun visitSymbol(node: Symbol): T
 
   fun visitSymbolReference(node: SymbolReference): T

ast/src/main/kotlin/gay/pizza/pork/ast/NodeVisitorExtensions.kt

@@ -20,6 +20,7 @@ fun <T> NodeVisitor<T>.visit(node: Node): T =
     is ListLiteral -> visitListLiteral(node)
     is Parentheses -> visitParentheses(node)
     is PrefixOperation -> visitPrefixOperation(node)
+    is SuffixOperation -> visitSuffixOperation(node)
     is StringLiteral -> visitStringLiteral(node)
     is SymbolReference -> visitSymbolReference(node)
     is While -> visitWhile(node)

ast/src/main/kotlin/gay/pizza/pork/ast/PrefixOperator.kt

@@ -7,5 +7,7 @@ import kotlinx.serialization.Serializable
 @Serializable
 @SerialName("prefixOperator")
 enum class PrefixOperator(val token: String) {
-  Negate("!")
+  Negate("!"),
+  UnaryPlus("+"),
+  UnaryMinus("-")
 }

ast/src/main/kotlin/gay/pizza/pork/ast/SuffixOperation.kt

@@ -0,0 +1,29 @@
+// GENERATED CODE FROM PORK AST CODEGEN
+package gay.pizza.pork.ast
+
+import kotlinx.serialization.SerialName
+import kotlinx.serialization.Serializable
+
+@Serializable
+@SerialName("suffixOperation")
+class SuffixOperation(val op: SuffixOperator, val reference: SymbolReference) : Expression() {
+  override val type: NodeType = NodeType.SuffixOperation
+
+  override fun <T> visitChildren(visitor: NodeVisitor<T>): List<T> =
+    visitor.visitNodes(reference)
+
+  override fun <T> visit(visitor: NodeVisitor<T>): T =
+    visitor.visitSuffixOperation(this)
+
+  override fun equals(other: Any?): Boolean {
+    if (other !is SuffixOperation) return false
+    return other.op == op && other.reference == reference
+  }
+
+  override fun hashCode(): Int {
+    var result = op.hashCode()
+    result = 31 * result + reference.hashCode()
+    result = 31 * result + type.hashCode()
+    return result
+  }
+}

ast/src/main/kotlin/gay/pizza/pork/ast/SuffixOperator.kt

@@ -0,0 +1,12 @@
+// GENERATED CODE FROM PORK AST CODEGEN
+package gay.pizza.pork.ast
+
+import kotlinx.serialization.SerialName
+import kotlinx.serialization.Serializable
+
+@Serializable
+@SerialName("suffixOperator")
+enum class SuffixOperator(val token: String) {
+  Increment("++"),
+  Decrement("--")
+}

evaluator/src/main/kotlin/gay/pizza/pork/evaluator/EvaluationVisitor.kt

@@ -71,9 +71,65 @@ class EvaluationVisitor(root: Scope) : NodeVisitor<Any> {
         }
         !value
       }
+      PrefixOperator.UnaryPlus, PrefixOperator.UnaryMinus -> {
+        if (value !is Number) {
+          throw RuntimeException("Numeric unary '${node.op.token}' illegal on non-numeric type '${value.javaClass.simpleName}'")
+        }
+        unaryNumericOperation(node, value)
+      }
     }
   }
 
+  private fun unaryNumericOperation(node: PrefixOperation, value: Number) = when (value) {
+    is Double -> {
+      unaryNumericOperation(
+        node.op,
+        value,
+        convert = { it.toDouble() },
+        plus = { +it },
+        minus = { -it }
+      )
+    }
+    is Float -> {
+      unaryNumericOperation(
+        node.op,
+        value,
+        convert = { it.toFloat() },
+        plus = { +it },
+        minus = { -it }
+      )
+    }
+    is Long -> {
+      unaryNumericOperation(
+        node.op,
+        value,
+        convert = { it.toLong() },
+        plus = { +it },
+        minus = { -it }
+      )
+    }
+    is Int -> {
+      unaryNumericOperation(
+        node.op,
+        value,
+        convert = { it.toInt() },
+        plus = { +it },
+        minus = { -it }
+      )
+    }
+    else -> throw RuntimeException("Unknown numeric type: ${value.javaClass.name}")
+  }
+
+  override fun visitSuffixOperation(node: SuffixOperation): Any {
+    val previousValue = currentScope.value(node.reference.symbol.id)
+    val infix = visitInfixOperation(InfixOperation(node.reference, when (node.op) {
+      SuffixOperator.Increment -> InfixOperator.Plus
+      SuffixOperator.Decrement -> InfixOperator.Minus
+    }, IntegerLiteral(1)))
+    currentScope.set(node.reference.symbol.id, infix)
+    return previousValue
+  }
+
   override fun visitSetAssignment(node: SetAssignment): Any {
     val value = node.value.visit(this)
     currentScope.set(node.symbol.id, value)
@@ -219,6 +275,20 @@ class EvaluationVisitor(root: Scope) : NodeVisitor<Any> {
     }
   }
 
+  private inline fun <T: Number> unaryNumericOperation(
+    op: PrefixOperator,
+    value: Number,
+    convert: (Number) -> T,
+    plus: (T) -> T,
+    minus: (T) -> T
+  ): Any {
+    return when (op) {
+      PrefixOperator.UnaryPlus -> plus(convert(value))
+      PrefixOperator.UnaryMinus -> minus(convert(value))
+      else -> throw RuntimeException("Unable to handle operation $op")
+    }
+  }
+
   override fun visitBlock(node: Block): BlockFunction = BlockFunction {
     var value: Any? = null
     for (expression in node.expressions) {

evaluator/src/main/kotlin/gay/pizza/pork/evaluator/InternalNativeProvider.kt

@@ -2,6 +2,7 @@ package gay.pizza.pork.evaluator
 
 class InternalNativeProvider(val quiet: Boolean = false) : NativeProvider {
   private val functions = mutableMapOf(
+    "print" to CallableFunction(::printValues),
     "println" to CallableFunction(::printLine)
   )
 
@@ -9,15 +10,15 @@ class InternalNativeProvider(val quiet: Boolean = false) : NativeProvider {
     return functions[definition] ?: throw RuntimeException("Unknown Internal Function: $definition")
   }
 
+  private fun printValues(arguments: Arguments): Any {
+    if (quiet || arguments.values.isEmpty()) return None
+    print(arguments.values.joinToString(" "))
+    return None
+  }
+
   private fun printLine(arguments: Arguments): Any {
-    if (quiet) {
-      return None
-    }
-    when (arguments.values.count()) {
-      0 -> println()
-      1 -> println(arguments.values[0])
-      else -> println(arguments.values.joinToString(" "))
-    }
+    if (quiet) return None
+    println(arguments.values.joinToString(" "))
     return None
   }
 }

examples/suffix.pork

@@ -0,0 +1,20 @@
+/* Barber shop sign generator! */
+func generatePole(width, height) {
+  var i = 0
+  while i < height {
+    let index = i++ mod width
+    var j = 0
+    while j < width {
+      if j == index { print("#") } else { print("_") }
+      j++
+    }
+    println()
+  }
+}
+
+export func main() {
+  println("nobody:")
+  println()
+  println("barber pole:")
+  generatePole(6, 18)
+}

examples/unary.pork

@@ -0,0 +1,6 @@
+export func main() {
+  let constant = -42
+  println("constant set by unary minus:     ", constant)
+  println("constant modified by unary minus:", -constant)
+  println("constant modified by unary plus: ", +constant)
+}

parser/src/main/kotlin/gay/pizza/pork/parser/Parser.kt

@@ -66,7 +66,12 @@ class Parser(source: PeekableSource<Token>, val attribution: NodeAttribution) {
       expect(TokenType.RightParentheses)
       FunctionCall(symbol, arguments)
     } else {
-      SymbolReference(symbol)
+      val reference = SymbolReference(symbol)
+      if (peek(TokenType.PlusPlus, TokenType.MinusMinus)) {
+        expect(TokenType.PlusPlus, TokenType.MinusMinus) {
+          SuffixOperation(convertSuffixOperator(it), reference)
+        }
+      } else reference
     }
   }
 
@@ -78,8 +83,8 @@ class Parser(source: PeekableSource<Token>, val attribution: NodeAttribution) {
   }
 
   private fun readPrefixOperation(): PrefixOperation = within {
-    expect(TokenType.Negation) {
-      PrefixOperation(PrefixOperator.Negate, readExpression())
+    expect(TokenType.Negation, TokenType.Plus, TokenType.Minus) {
+      PrefixOperation(convertPrefixOperator(it), readExpression())
     }
   }
 
@@ -143,7 +148,7 @@ class Parser(source: PeekableSource<Token>, val attribution: NodeAttribution) {
         readParentheses()
       }
 
-      TokenType.Negation -> {
+      TokenType.Negation, TokenType.Plus, TokenType.Minus -> {
         readPrefixOperation()
       }
 
@@ -288,22 +293,33 @@ class Parser(source: PeekableSource<Token>, val attribution: NodeAttribution) {
     }
   }
 
-  private fun convertInfixOperator(token: Token): InfixOperator =
-    when (token.type) {
-      TokenType.Plus -> InfixOperator.Plus
-      TokenType.Minus -> InfixOperator.Minus
-      TokenType.Multiply -> InfixOperator.Multiply
-      TokenType.Divide -> InfixOperator.Divide
-      TokenType.Equality -> InfixOperator.Equals
-      TokenType.Inequality -> InfixOperator.NotEquals
-      TokenType.Mod -> InfixOperator.EuclideanModulo
-      TokenType.Rem -> InfixOperator.Remainder
-      TokenType.Lesser -> InfixOperator.Lesser
-      TokenType.Greater -> InfixOperator.Greater
-      TokenType.LesserEqual -> InfixOperator.LesserEqual
-      TokenType.GreaterEqual -> InfixOperator.GreaterEqual
-      else -> throw RuntimeException("Unknown Infix Operator")
-    }
+  private fun convertInfixOperator(token: Token): InfixOperator = when (token.type) {
+    TokenType.Plus -> InfixOperator.Plus
+    TokenType.Minus -> InfixOperator.Minus
+    TokenType.Multiply -> InfixOperator.Multiply
+    TokenType.Divide -> InfixOperator.Divide
+    TokenType.Equality -> InfixOperator.Equals
+    TokenType.Inequality -> InfixOperator.NotEquals
+    TokenType.Mod -> InfixOperator.EuclideanModulo
+    TokenType.Rem -> InfixOperator.Remainder
+    TokenType.Lesser -> InfixOperator.Lesser
+    TokenType.Greater -> InfixOperator.Greater
+    TokenType.LesserEqual -> InfixOperator.LesserEqual
+    TokenType.GreaterEqual -> InfixOperator.GreaterEqual
+    else -> throw RuntimeException("Unknown Infix Operator")
+  }
+
+  private fun convertPrefixOperator(token: Token): PrefixOperator = when (token.type) {
+    TokenType.Plus -> PrefixOperator.UnaryPlus
+    TokenType.Minus -> PrefixOperator.UnaryMinus
+    else -> throw RuntimeException("Unknown Prefix Operator")
+  }
+
+  private fun convertSuffixOperator(token: Token): SuffixOperator = when (token.type) {
+    TokenType.PlusPlus -> SuffixOperator.Increment
+    TokenType.MinusMinus -> SuffixOperator.Decrement
+    else -> throw RuntimeException("Unknown Suffix Operator")
+  }
 
   fun readCompilationUnit(): CompilationUnit = within {
     val declarations = mutableListOf<Declaration>()

parser/src/main/kotlin/gay/pizza/pork/parser/Printer.kt

@@ -120,6 +120,11 @@ class Printer(buffer: StringBuilder) : NodeVisitor<Unit> {
     visit(node.expression)
   }
 
+  override fun visitSuffixOperation(node: SuffixOperation) {
+    visit(node.reference)
+    append(node.op.token)
+  }
+
   override fun visitSetAssignment(node: SetAssignment) {
     visit(node.symbol)
     append(" = ")

parser/src/main/kotlin/gay/pizza/pork/parser/TokenType.kt

@@ -15,8 +15,10 @@ enum class TokenType(vararg properties: TokenTypeProperty) {
   Equality(OperatorFamily),
   Inequality(OperatorFamily),
   Equals(SingleChar('='), Promotion('=', Equality)),
-  Plus(SingleChar('+'), OperatorFamily),
-  Minus(SingleChar('-'), OperatorFamily),
+  PlusPlus(ManyChars("++"), OperatorFamily),
+  MinusMinus(ManyChars("--"), OperatorFamily),
+  Plus(SingleChar('+'), OperatorFamily, Promotion('+', PlusPlus)),
+  Minus(SingleChar('-'), OperatorFamily, Promotion('-', MinusMinus)),
   Multiply(SingleChar('*'), OperatorFamily),
   Divide(SingleChar('/'), OperatorFamily),
   LesserEqual(OperatorFamily),

parser/src/main/kotlin/gay/pizza/pork/parser/Tokenizer.kt

@@ -9,6 +9,7 @@ class Tokenizer(val source: CharSource) {
       var endOfComment = false
       while (true) {
         val char = source.next()
+        if (char == CharSource.NullChar) throw RuntimeException("Unterminated block comment")
         append(char)
 
         if (endOfComment) {

stdlib/src/main/pork/lang/prelude.pork

@@ -1,2 +1,5 @@
-export func println(messages...)
+export func print(values...)
+  native internal "print"
+
+export func println(values...)
   native internal "println"