Initial Array Access Implementation

Signed-off-by: Will Hawkins <hawkinsw@obs.cr>

Sources/Common/Execution.swift

@@ -17,10 +17,17 @@
 
 open class ProgramExecution: CustomStringConvertible {
   public var scopes: ValueScopes = ValueScopes()
+  let initialValues: ValueScopes?
   var error: Error?
   var debug: DebugLevel = DebugLevel.Error
 
-  public init() {}
+  public init() {
+    initialValues = .none
+  }
+
+  public init(withGlobalValues values: ValueScopes) {
+    initialValues = values
+  }
 
   open var description: String {
     return "Runtime:\nScopes: \(scopes)"
@@ -80,6 +87,10 @@ open class ProgramExecution: CustomStringConvertible {
     new_pe.scopes = new_scopes
     return new_pe
   }
+
+  public func initial_values() -> ValueScopes? {
+    return self.initialValues
+  }
 }
 
 public typealias ValueScope = Scope<P4Value>

Sources/Common/ProgramTypes.swift

@@ -198,8 +198,12 @@ public class P4IntValue: P4Value {
   public init(withValue value: Int) {
     self.value = value
   }
+
+  public func access() -> Int {
+    return self.value
+  }
+
   public func eq(rhs: P4Value) -> Bool {
-    print("Int value equal.")
     guard let int_rhs = rhs as? P4IntValue else {
       return false
     }
@@ -251,3 +255,49 @@ public class P4StringValue: P4Value {
 public class Packet {
   public init() {}
 }
+
+/// A P4 array type
+public struct P4Array: P4Type {
+
+  public static func create() -> any P4Type {
+    return P4Array()
+  }
+  public var description: String {
+    return "Array"
+  }
+  public func eq(rhs: any P4Type) -> Bool {
+    return switch rhs {
+    case is P4Array: true
+    default: false
+    }
+  }
+}
+
+/// An instance of a P4 array
+public class P4ArrayValue: P4Value {
+  public func type() -> any P4Type {
+    return P4Array()
+  }
+
+  let value: Array<EvaluatableExpression>
+
+  public init(withValue value: Array<EvaluatableExpression>) {
+    self.value = value
+  }
+
+  public func access(_ index: Int) -> EvaluatableExpression {
+    return self.value[index]
+  }
+
+  public func eq(rhs: P4Value) -> Bool {
+    guard let _ = rhs as? P4ArrayValue else {
+      return false
+    }
+    // TODO!!
+    return true
+  }
+
+  public var description: String {
+    "\(self.value) of \(self.type()) type"
+  }
+}

Sources/Common/Scope.swift

@@ -16,10 +16,10 @@
 // along with this program. If not, see <https://www.gnu.org/licenses/>.
 
 public struct Scope<T>: CustomStringConvertible, Sequence {
-  public typealias Element = T
-  public typealias Iterator = Dictionary<Identifier, T>.Values.Iterator
+  public typealias Element = (key: Identifier, value: T)
+  public typealias Iterator = Dictionary<Identifier, T>.Iterator
   public func makeIterator() -> Iterator {
-    self.symbols.values.makeIterator()
+    self.symbols.makeIterator()
   }
 
   var symbols: [Identifier: T] = Dictionary()
@@ -123,8 +123,8 @@ public struct Scopes<T>: CustomStringConvertible, Sequence {
     return .Error(Error(withMessage: "Cannot find \(identifier) in lexical scope."))
   }
 
-  public typealias Element = T
-  public typealias Iterator = Dictionary<Identifier, T>.Values.Iterator
+  public typealias Element = (key: Identifier, value: T)
+  public typealias Iterator = Dictionary<Identifier, T>.Iterator
   public func makeIterator() -> Iterator {
     scopes.last?.makeIterator() ?? Scope<T>().makeIterator()
   }