Refactor Parsing/Runtime

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

Sources/Common/Execution.swift

@@ -16,7 +16,7 @@
 // along with this program. If not, see <https://www.gnu.org/licenses/>.
 
 open class ProgramExecution: CustomStringConvertible {
-    public var scopes: Scopes = Scopes()
+    public var scopes: ValueScopes = ValueScopes()
     var error: Error?
     var debug: DebugLevel = DebugLevel.Error
 
@@ -75,130 +75,5 @@ open class ProgramExecution: CustomStringConvertible {
 
 }
 
-
-public struct Scope: CustomStringConvertible, Equatable {
-    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 set(identifier: Identifier, value: P4Value) -> Scope? {
-        var updated = false
-        var updated_scope: [Variable] = Array()
-        for v in variables {
-            if v == identifier && v.value_type.type().eq(rhs: value.type()) {
-                updated = true
-                updated_scope.append(Variable(name: v.name, withValue: value, isConstant: false))
-            } else {
-                updated_scope.append(v)
-            }
-        }
-        var new_scope = Scope()
-        new_scope.variables = updated_scope
-        return if updated {
-            new_scope
-        } else {
-            .none
-        }
-    }
-
-    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, Equatable {
-    var scopes: [Scope] = Array()
-
-    public init() {}
-
-    init(withScopes scopes: [Scope]) {
-        self.scopes = scopes
-    }
-
-    public func enter() -> Scopes {
-        var new_scopes = scopes
-        new_scopes.append(Scope())
-
-        return Scopes(withScopes: new_scopes)
-    }
-
-    public func exit() -> Scopes {
-        var old_scopes = scopes
-        _ = old_scopes.popLast()
-        return Scopes(withScopes: old_scopes)
-    }
-
-    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 func evaluate(identifier: Identifier) -> Result<P4Value> {
-        for scope in scopes {
-            if let vari = scope.lookup(identifier: identifier) {
-                return .Ok(vari.value)
-            }
-        }
-        return .Error(Error(withMessage: "Cannot find \(identifier) in scope."))
-    }
-
-    public var count: Int {
-        get {
-            scopes.count
-        }
-    }
-
-    public func set(identifier: Identifier, value: P4Value) -> Scopes {
-        var new_scopes: [Scope] = Array()
-        for scope in self.scopes {
-            if let updated_scope = scope.set(identifier: identifier, value: value) {
-                new_scopes.append(updated_scope)
-            } else {
-                new_scopes.append(scope)
-            }
-        }
-        return Scopes(withScopes: new_scopes)
-    }
-}
+public typealias ValueScope = Scope<P4Value>
+public typealias ValueScopes = Scopes<P4Value>