Refactor

Refactor into four major components:

1. Common: Things shared among all other components.
2. Lang: P4-language-related components.
3. Runtime: Components required to run a P4 program.
4. Parser: Components for parsing a P4 program from source.

Other components:

1. Macros
2. Tests
3. TreeSitterExtensions: Extra tree sitter functionality

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

Sources/Common/Execution.swift

@@ -0,0 +1,104 @@
+// p4rse, Copyright 2026, Will Hawkins
+//
+// This file is part of p4rse.
+//
+// This file is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program. If not, see <https://www.gnu.org/licenses/>.
+
+open class ProgramExecution: CustomStringConvertible {
+    public var scopes: Scopes = Scopes()
+
+    public init() {}
+
+    open var description: String {
+        return "Runtime:\nScopes: \(scopes)"
+    }
+}
+
+
+public struct Scope: CustomStringConvertible{
+    var variables: [Variable] = Array()
+    public init() {}
+
+    public var description: String {
+        var result = String()
+        for v in variables {
+            result += "\(v)\n"
+        }
+        return result
+    }
+
+    public var count: Int {
+        get {
+            variables.count
+        }
+    }
+
+    public func lookup(identifier: Identifier) -> Variable? {
+        for v in variables {
+            if v == identifier {
+                return v
+            }
+        }
+        return .none
+    }
+
+    public mutating func declare(variable: Variable) -> Scope {
+        var s = self
+        s.variables.append(variable)
+        return s
+    }
+}
+
+public struct Scopes: CustomStringConvertible {
+    var scopes: [Scope] = Array()
+
+    public init() {}
+
+    public mutating func enter() {
+        scopes.append(Scope())
+    }
+
+    public mutating func exit() {
+        let _ = scopes.popLast()
+    }
+
+    public var description: String {
+        var result = String()
+        for s in scopes {
+            result += "Scope:\n\(s)\n"
+        }
+
+        return result
+    }
+
+    public var current: Scope? {
+        get {
+            scopes.last
+        }
+    }
+
+    public func declare(variable: Variable) -> Scopes {
+        var s = self
+        if var scope = s.scopes.popLast() {
+            s.scopes.append(scope.declare(variable: variable))
+        }
+        return s
+    }
+
+    public var count: Int {
+        get {
+            scopes.count
+        }
+    }
+}

Sources/Common/ProgramTypes.swift

@@ -0,0 +1,99 @@
+// p4rse, Copyright 2026, Will Hawkins
+//
+// This file is part of p4rse.
+//
+// This file is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program. If not, see <https://www.gnu.org/licenses/>.
+
+
+public class Identifier: CustomStringConvertible, Equatable {
+    var name: String
+
+    public init(name: String) {
+        self.name = name
+    }
+
+    public var description: String {
+        return "\(name)"
+    }
+
+    public static func ==(lhs: Identifier, rhs: Identifier) -> Bool {
+        return lhs.name == rhs.name
+    }
+}
+
+public class Variable: Identifier {
+    var constant: Bool
+    var value: ValueType
+
+    public init(name: String, withValue value: ValueType, isConstant constant: Bool) {
+        self.constant = constant
+        self.value = value
+        super.init(name: name)
+    }
+
+    public override var description: String {
+        return "\(super.description) = \(value) \(constant ? "(constant)" : "")"
+    }
+
+    public var value_type: ValueType {
+        get {
+            value
+        }
+    }
+}
+
+public enum ValueType: CustomStringConvertible, Equatable {
+    case Boolean(Bool)
+    case Int(Int)
+    case String(String)
+
+    public var description: String {
+        switch self {
+            case ValueType.Boolean(let b):
+                return "\(b) of Boolean"
+            case ValueType.Int(let i):
+                return "\(i) of Int"
+            case ValueType.String(let s):
+                return "\(s) of String"
+        }
+    }
+
+    public static func==(lhs: ValueType, rhs: ValueType) -> Bool {
+        switch (lhs,rhs) {
+            case (ValueType.Boolean(let lhsb), ValueType.Boolean(let rhsb)):
+                return lhsb == rhsb
+            case (ValueType.String(let lhsb), ValueType.String(let rhsb)):
+                return lhsb == rhsb
+            case (ValueType.Int(let lhsb), ValueType.Int(let rhsb)):
+                return lhsb == rhsb
+            default: return false
+        }
+    }
+
+}
+
+public struct Value: CustomStringConvertible {
+    public var value_type: ValueType
+
+    public init(withValue value: ValueType) {
+        self.value_type = value
+    }
+    public var description: String {
+        return "\(value_type)"
+    }
+}
+
+public class Packet {
+    public init() {}
+}

Sources/Common/Protocols.swift

@@ -0,0 +1,33 @@
+// p4rse, Copyright 2026, Will Hawkins
+//
+// This file is part of p4rse.
+//
+// This file is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program. If not, see <https://www.gnu.org/licenses/>.
+
+public protocol EvaluatableExpression {
+    /// Evaluate an expression for a given execution
+    /// - Parameters
+    ///  - execution: The execution context in which to evaluate the expression
+    /// - Returns: The value of expression
+    func evaluate(execution: ProgramExecution) -> ValueType
+}
+
+public protocol EvaluatableParserStatement {
+    /// Evaluate a statement for a given execution
+    /// - Parameters
+    ///  - execution: The execution context in which to evaluate the parser statement
+    /// - Returns: An updated execution after evaluating the parser statement
+    func evaluate(execution: ProgramExecution) -> ProgramExecution
+}
+

Sources/Common/Support.swift

@@ -0,0 +1,85 @@
+// p4rse, Copyright 2026, Will Hawkins
+//
+// This file is part of p4rse.
+//
+// This file is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program. If not, see <https://www.gnu.org/licenses/>.
+
+public struct Error: Equatable {
+    public private(set) var msg: String
+
+    public init(withMessage msg: String) {
+        self.msg = msg
+    }
+}
+
+public struct Nothing: CustomStringConvertible {
+    public var description: String {
+        return "Nothing"
+    }
+
+    public init() {}
+}
+
+
+public enum Result<OKT>: Equatable {
+    case Ok(OKT)
+    case Error(Error)
+
+    public static func == (lhs: Result, rhs: Result) -> Bool {
+        switch (lhs, rhs) {
+        case (Ok, Ok):
+            return true
+        case (Error(let le), Error(let re)):
+            return le.msg == re.msg
+        default:
+            return false
+        }
+    }
+
+    public func error() -> Error? {
+        if case Result.Error(let e) = self {
+            return e
+        }
+        return nil
+    }
+}
+
+extension Result where OKT: CustomStringConvertible {
+    public var description: String {
+        switch self {
+            case Result.Error(let e):
+                return e.msg
+            case Result.Ok(let o):
+                return "\(o)"
+        }
+    }
+}
+
+extension Result {
+    public var description: String {
+        switch self {
+            case Result.Error(let e):
+                return e.msg
+            case Result.Ok(_):
+                return "Ok"
+        }
+    }
+}
+
+@freestanding(expression) public macro RequireOkResult<T>(_: Result<T>) -> Bool =
+    #externalMacro(module: "Macros", type: "RequireResult")
+@freestanding(expression) public macro RequireErrorResult<T>(_: Error, _: Result<T>) -> Bool =
+    #externalMacro(module: "Macros", type: "RequireErrorResult")
+@freestanding(expression) public macro UseOkResult<T>(_: Result<T>) -> T =
+    #externalMacro(module: "Macros", type: "UseOkResult")