Remove VisualScript module for 4.0

As announced in https://godotengine.org/article/godot-4-will-discontinue-visual-scripting,
Godot maintainers have agreed to discontinue the current implementation of
our VisualScript language.

The way it had been designed was not user-friendly enough and we did not
succeed in improving its usability to actually make it a good low-code
solution for users who need one.

So we prefer to remove it for Godot 4.0 and leave the door open for new,
innovative ideas around visual scripting, to be developed as plugins or
extensions now that Godot provides sufficient functionality for this
(notably via GDExtension and the godot-cpp C++ bindings).

The current module has been moved to a dedicated repository (with full Git
history extracted with `git filter-branch`):

https://github.com/godotengine/godot-visual-script

It can still be compiled as a C++ module (for now, but will likely require
work to be kept in sync with the engine repository), but our hope is that
contributors will port it to GDExtension (which is quite compatibile with
the existing C++ module code when using the godot-cpp C++ bindings).

1 files changed, 0 insertions, 284 deletions

diff --git a/modules/visual_script/visual_script_expression.h b/modules/visual_script/visual_script_expression.h
deleted file mode 100644
index 7e10f98f36..0000000000
--- a/modules/visual_script/visual_script_expression.h
+++ /dev/null
@@ -1,284 +0,0 @@
-/*************************************************************************/
-/*  visual_script_expression.h                                           */
-/*************************************************************************/
-/*                       This file is part of:                           */
-/*                           GODOT ENGINE                                */
-/*                      https://godotengine.org                          */
-/*************************************************************************/
-/* Copyright (c) 2007-2022 Juan Linietsky, Ariel Manzur.                 */
-/* Copyright (c) 2014-2022 Godot Engine contributors (cf. AUTHORS.md).   */
-/*                                                                       */
-/* Permission is hereby granted, free of charge, to any person obtaining */
-/* a copy of this software and associated documentation files (the       */
-/* "Software"), to deal in the Software without restriction, including   */
-/* without limitation the rights to use, copy, modify, merge, publish,   */
-/* distribute, sublicense, and/or sell copies of the Software, and to    */
-/* permit persons to whom the Software is furnished to do so, subject to */
-/* the following conditions:                                             */
-/*                                                                       */
-/* The above copyright notice and this permission notice shall be        */
-/* included in all copies or substantial portions of the Software.       */
-/*                                                                       */
-/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
-/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
-/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
-/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  */
-/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  */
-/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     */
-/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
-/*************************************************************************/
-
-#ifndef VISUAL_SCRIPT_EXPRESSION_H
-#define VISUAL_SCRIPT_EXPRESSION_H
-
-#include "visual_script.h"
-#include "visual_script_builtin_funcs.h"
-
-class VisualScriptExpression : public VisualScriptNode {
-	GDCLASS(VisualScriptExpression, VisualScriptNode);
-	friend class VisualScriptNodeInstanceExpression;
-
-	struct Input {
-		Variant::Type type = Variant::NIL;
-		String name;
-	};
-
-	Vector<Input> inputs;
-	Variant::Type output_type = Variant::NIL;
-
-	String expression;
-
-	bool sequenced = false;
-	int str_ofs = 0;
-	bool expression_dirty = true;
-
-	bool _compile_expression();
-
-	enum TokenType {
-		TK_CURLY_BRACKET_OPEN,
-		TK_CURLY_BRACKET_CLOSE,
-		TK_BRACKET_OPEN,
-		TK_BRACKET_CLOSE,
-		TK_PARENTHESIS_OPEN,
-		TK_PARENTHESIS_CLOSE,
-		TK_IDENTIFIER,
-		TK_BUILTIN_FUNC,
-		TK_SELF,
-		TK_CONSTANT,
-		TK_BASIC_TYPE,
-		TK_COLON,
-		TK_COMMA,
-		TK_PERIOD,
-		TK_OP_IN,
-		TK_OP_EQUAL,
-		TK_OP_NOT_EQUAL,
-		TK_OP_LESS,
-		TK_OP_LESS_EQUAL,
-		TK_OP_GREATER,
-		TK_OP_GREATER_EQUAL,
-		TK_OP_AND,
-		TK_OP_OR,
-		TK_OP_NOT,
-		TK_OP_ADD,
-		TK_OP_SUB,
-		TK_OP_MUL,
-		TK_OP_DIV,
-		TK_OP_MOD,
-		TK_OP_SHIFT_LEFT,
-		TK_OP_SHIFT_RIGHT,
-		TK_OP_BIT_AND,
-		TK_OP_BIT_OR,
-		TK_OP_BIT_XOR,
-		TK_OP_BIT_INVERT,
-		TK_EOF,
-		TK_ERROR,
-		TK_MAX
-	};
-
-	static const char *token_name[TK_MAX];
-	struct Token {
-		TokenType type;
-		Variant value;
-	};
-
-	void _set_error(const String &p_err) {
-		if (error_set) {
-			return;
-		}
-		error_str = p_err;
-		error_set = true;
-	}
-
-	Error _get_token(Token &r_token);
-
-	String error_str;
-	bool error_set = true;
-
-	struct ENode {
-		enum Type {
-			TYPE_INPUT,
-			TYPE_CONSTANT,
-			TYPE_SELF,
-			TYPE_OPERATOR,
-			TYPE_INDEX,
-			TYPE_NAMED_INDEX,
-			TYPE_ARRAY,
-			TYPE_DICTIONARY,
-			TYPE_CONSTRUCTOR,
-			TYPE_BUILTIN_FUNC,
-			TYPE_CALL
-		};
-
-		ENode *next = nullptr;
-
-		Type type = Type::TYPE_SELF;
-
-		virtual ~ENode() {
-			if (next) {
-				memdelete(next);
-			}
-		}
-	};
-
-	struct Expression {
-		bool is_op = false;
-		union {
-			Variant::Operator op;
-			ENode *node = nullptr;
-		};
-	};
-
-	ENode *_parse_expression();
-
-	struct InputNode : public ENode {
-		int index = 0;
-		InputNode() {
-			type = TYPE_INPUT;
-		}
-	};
-
-	struct ConstantNode : public ENode {
-		Variant value;
-		ConstantNode() {
-			type = TYPE_CONSTANT;
-		}
-	};
-
-	struct OperatorNode : public ENode {
-		Variant::Operator op = Variant::Operator::OP_ADD;
-
-		ENode *nodes[2] = { nullptr, nullptr };
-
-		OperatorNode() {
-			type = TYPE_OPERATOR;
-		}
-	};
-
-	struct SelfNode : public ENode {
-		SelfNode() {
-			type = TYPE_SELF;
-		}
-	};
-
-	struct IndexNode : public ENode {
-		ENode *base = nullptr;
-		ENode *index = nullptr;
-
-		IndexNode() {
-			type = TYPE_INDEX;
-		}
-	};
-
-	struct NamedIndexNode : public ENode {
-		ENode *base = nullptr;
-		StringName name;
-
-		NamedIndexNode() {
-			type = TYPE_NAMED_INDEX;
-		}
-	};
-
-	struct ConstructorNode : public ENode {
-		Variant::Type data_type = Variant::Type::NIL;
-		Vector<ENode *> arguments;
-
-		ConstructorNode() {
-			type = TYPE_CONSTRUCTOR;
-		}
-	};
-
-	struct CallNode : public ENode {
-		ENode *base = nullptr;
-		StringName method;
-		Vector<ENode *> arguments;
-
-		CallNode() {
-			type = TYPE_CALL;
-		}
-	};
-
-	struct ArrayNode : public ENode {
-		Vector<ENode *> array;
-		ArrayNode() {
-			type = TYPE_ARRAY;
-		}
-	};
-
-	struct DictionaryNode : public ENode {
-		Vector<ENode *> dict;
-		DictionaryNode() {
-			type = TYPE_DICTIONARY;
-		}
-	};
-
-	struct BuiltinFuncNode : public ENode {
-		VisualScriptBuiltinFunc::BuiltinFunc func = VisualScriptBuiltinFunc::BuiltinFunc::BYTES_TO_VAR;
-		Vector<ENode *> arguments;
-		BuiltinFuncNode() {
-			type = TYPE_BUILTIN_FUNC;
-		}
-	};
-
-	template <class T>
-	T *alloc_node() {
-		T *node = memnew(T);
-		node->next = nodes;
-		nodes = node;
-		return node;
-	}
-
-	ENode *root = nullptr;
-	ENode *nodes = nullptr;
-
-protected:
-	bool _set(const StringName &p_name, const Variant &p_value);
-	bool _get(const StringName &p_name, Variant &r_ret) const;
-	void _get_property_list(List<PropertyInfo> *p_list) const;
-
-public:
-	virtual void reset_state() override;
-
-	virtual int get_output_sequence_port_count() const override;
-	virtual bool has_input_sequence_port() const override;
-
-	virtual String get_output_sequence_port_text(int p_port) const override;
-
-	virtual int get_input_value_port_count() const override;
-	virtual int get_output_value_port_count() const override;
-
-	virtual PropertyInfo get_input_value_port_info(int p_idx) const override;
-	virtual PropertyInfo get_output_value_port_info(int p_idx) const override;
-
-	virtual String get_caption() const override;
-	virtual String get_text() const override;
-	virtual String get_category() const override { return "operators"; }
-
-	virtual VisualScriptNodeInstance *instantiate(VisualScriptInstance *p_instance) override;
-
-	VisualScriptExpression();
-	~VisualScriptExpression();
-};
-
-void register_visual_script_expression_node();
-
-#endif // VISUAL_SCRIPT_EXPRESSION_H