Open xmnlab opened 3 hours ago
Alternative with plum multiple dispatching (from gpt):
First, ensure you have the Plum library installed. You can install it using pip
:
pip install plum-dispatch
Assuming your project structure resembles the following:
your_project/
├── astx/
│ ├── __init__.py
│ ├── base.py
│ ├── expressions.py
│ ├── literals.py
│ ├── types.py
│ ├── variables.py
│ └── enums.py
└── astx2python.py
Create a new file named astx2python.py
and import the required classes and functions from astx
and plum
:
# astx2python.py
from plum import dispatch
from astx.base import ASTNodes, ASTKind
from astx.literals import (
LiteralInt32,
LiteralString,
LiteralBoolean,
LiteralChar,
)
from astx.types import (
Char,
String,
TypeExpr,
)
from astx.expressions import (
BinaryOp,
UnaryOp,
AssignmentExpr,
TypeCastExpr,
AwaitExpr,
YieldExpr,
MatchExpr,
IndexExpr,
SliceExpr,
MemberAccessExpr,
TypeExpr,
)
from astx.variables import Variable, VariableAssignment, VariableDeclaration
from astx.blocks import Block
from astx.functions import FunctionDef, AsyncFunctionDef
from astx.enums import EncodingKind
# Import other necessary astx classes as needed
The ASTxToPythonGenerator
class will manage the code generation process, maintaining the current indentation level and providing helper methods.
# astx2python.py
class ASTxToPythonGenerator:
"""Transpiler that converts ASTx nodes to Python code."""
def __init__(self):
self.indent_level = 0
self.indent_str = " " # 4 spaces
def generate(self, node: ASTNodes) -> str:
"""Generate Python code from an ASTx node."""
return visit(self, node)
def _generate_block(self, block: Block) -> str:
"""Generate code for a block of statements with proper indentation."""
self.indent_level += 1
indent = self.indent_str * self.indent_level
lines = [indent + self.generate(stmt) for stmt in block.nodes]
self.indent_level -= 1
return "\n".join(lines) if lines else self.indent_str * self.indent_level + "pass"
Using Plum's multiple dispatch, define a single visit
function that dispatches based on the type of the AST node. Each specific handler will process a particular AST node type.
# astx2python.py
@dispatch(ASTxToPythonGenerator, LiteralInt32)
def visit(generator: ASTxToPythonGenerator, node: LiteralInt32) -> str:
"""Handle LiteralInt32 nodes."""
return str(node.value)
@dispatch(ASTxToPythonGenerator, LiteralString)
def visit(generator: ASTxToPythonGenerator, node: LiteralString) -> str:
"""Handle LiteralString nodes."""
# Optionally handle different encodings
return f"'{node.value}'"
@dispatch(ASTxToPythonGenerator, LiteralBoolean)
def visit(generator: ASTxToPythonGenerator, node: LiteralBoolean) -> str:
"""Handle LiteralBoolean nodes."""
return "True" if node.value else "False"
@dispatch(ASTxToPythonGenerator, LiteralChar)
def visit(generator: ASTxToPythonGenerator, node: LiteralChar) -> str:
"""Handle LiteralChar nodes."""
return f"'{node.value}'"
@dispatch(ASTxToPythonGenerator, Variable)
def visit(generator: ASTxToPythonGenerator, node: Variable) -> str:
"""Handle Variable nodes."""
return node.name
@dispatch(ASTxToPythonGenerator, VariableAssignment)
def visit(generator: ASTxToPythonGenerator, node: VariableAssignment) -> str:
"""Handle VariableAssignment nodes."""
target = generator.generate(node.target) if isinstance(node.target, ASTNodes) else node.target
value = generator.generate(node.value)
return f"{target} = {value}"
@dispatch(ASTxToPythonGenerator, BinaryOp)
def visit(generator: ASTxToPythonGenerator, node: BinaryOp) -> str:
"""Handle BinaryOp nodes."""
lhs = generator.generate(node.lhs)
rhs = generator.generate(node.rhs)
return f"({lhs} {node.op_code} {rhs})"
@dispatch(ASTxToPythonGenerator, UnaryOp)
def visit(generator: ASTxToPythonGenerator, node: UnaryOp) -> str:
"""Handle UnaryOp nodes."""
operand = generator.generate(node.operand)
return f"({node.op_code}{operand})"
@dispatch(ASTxToPythonGenerator, FunctionDef)
def visit(generator: ASTxToPythonGenerator, node: FunctionDef) -> str:
"""Handle FunctionDef nodes."""
params = ", ".join(arg.name for arg in node.args.args)
returns = f" -> {generator.generate(node.returns)}" if node.returns else ""
decorators = "\n".join(f"@{generator.generate(dec)}" for dec in node.decorators) if node.decorators else ""
header = f"def {node.name}({params}){returns}:"
body = generator._generate_block(node.body)
return f"{decorators}\n{header}\n{body}" if decorators else f"{header}\n{body}"
@dispatch(ASTxToPythonGenerator, AsyncFunctionDef)
def visit(generator: ASTxToPythonGenerator, node: AsyncFunctionDef) -> str:
"""Handle AsyncFunctionDef nodes."""
params = ", ".join(arg.name for arg in node.args.args)
returns = f" -> {generator.generate(node.returns)}" if node.returns else ""
decorators = "\n".join(f"@{generator.generate(dec)}" for dec in node.decorators) if node.decorators else ""
header = f"async def {node.name}({params}){returns}:"
body = generator._generate_block(node.body)
return f"{decorators}\n{header}\n{body}" if decorators else f"{header}\n{body}"
@dispatch(ASTxToPythonGenerator, Block)
def visit(generator: ASTxToPythonGenerator, node: Block) -> str:
"""Handle Block nodes."""
return generator._generate_block(node)
@dispatch(ASTxToPythonGenerator, TypeCastExpr)
def visit(generator: ASTxToPythonGenerator, node: TypeCastExpr) -> str:
"""Handle TypeCastExpr nodes."""
target_type = generator.generate(node.target_type)
expr = generator.generate(node.expr)
return f"{target_type}({expr})"
@dispatch(ASTxToPythonGenerator, AwaitExpr)
def visit(generator: ASTxToPythonGenerator, node: AwaitExpr) -> str:
"""Handle AwaitExpr nodes."""
value = generator.generate(node.value)
return f"await {value}"
@dispatch(ASTxToPythonGenerator, YieldExpr)
def visit(generator: ASTxToPythonGenerator, node: YieldExpr) -> str:
"""Handle YieldExpr nodes."""
value = generator.generate(node.value) if node.value else ""
return f"yield {value}"
@dispatch(ASTxToPythonGenerator, MatchExpr)
def visit(generator: ASTxToPythonGenerator, node: MatchExpr) -> str:
"""Handle MatchExpr nodes."""
# Python 3.10+ supports match statements
value = generator.generate(node.value)
arms = "\n".join(
f" case {generator.generate(pattern)}: return {generator.generate(expr)}"
for pattern, expr in node.arms
)
return f"match {value}:\n{arms}"
@dispatch(ASTxToPythonGenerator, IndexExpr)
def visit(generator: ASTxToPythonGenerator, node: IndexExpr) -> str:
"""Handle IndexExpr nodes."""
collection = generator.generate(node.value)
if isinstance(node.index, list):
indices = ", ".join(generator.generate(idx) for idx in node.index)
return f"{collection}[{indices}]"
else:
index = generator.generate(node.index)
return f"{collection}[{index}]"
@dispatch(ASTxToPythonGenerator, SliceExpr)
def visit(generator: ASTxToPythonGenerator, node: SliceExpr) -> str:
"""Handle SliceExpr nodes."""
lower = generator.generate(node.lower) if node.lower else ""
upper = generator.generate(node.upper) if node.upper else ""
step = generator.generate(node.step) if node.step else ""
if step:
return f"{lower}:{upper}:{step}"
else:
return f"{lower}:{upper}"
@dispatch(ASTxToPythonGenerator, MemberAccessExpr)
def visit(generator: ASTxToPythonGenerator, node: MemberAccessExpr) -> str:
"""Handle MemberAccessExpr nodes."""
value = generator.generate(node.value)
attr = node.attr
return f"{value}.{attr}"
@dispatch(ASTxToPythonGenerator, Char)
def visit(generator: ASTxToPythonGenerator, node: Char) -> str:
"""Handle Char type nodes."""
return "str" # Python's str represents characters
@dispatch(ASTxToPythonGenerator, String)
def visit(generator: ASTxToPythonGenerator, node: String) -> str:
"""Handle String type nodes."""
return "str"
@dispatch(ASTxToPythonGenerator, TypeExpr)
def visit(generator: ASTxToPythonGenerator, node: TypeExpr) -> str:
"""Handle TypeExpr nodes."""
return generator.generate(node.type)
@dispatch(ASTxToPythonGenerator, TypeAliasStmt)
def visit(generator: ASTxToPythonGenerator, node: TypeAliasStmt) -> str:
"""Handle TypeAliasStmt nodes."""
name = node.name
if node.type_params:
params = "[" + ", ".join(node.type_params) + "]"
else:
params = ""
aliased_type = generator.generate(node.aliased_type)
return f"{name}{params} = {aliased_type}"
@dispatch(ASTxToPythonGenerator, GotoStmt)
def visit(generator: ASTxToPythonGenerator, node: GotoStmt) -> str:
"""Handle GotoStmt nodes."""
# Python does not support goto statements; using exceptions or other control flows instead
# For testing purposes, we can represent it as a comment
return f"# goto {node.label}"
# Add more visit functions as needed for other AST node types
If you encounter AST node types that aren't directly translatable to Python or are unsupported, you can handle them gracefully, perhaps by inserting comments or raising exceptions.
@dispatch(ASTxToPythonGenerator, ASTNodes)
def visit(generator: ASTxToPythonGenerator, node: ASTNodes) -> str:
"""Handle unsupported or generic ASTNodes."""
return f"# Unsupported AST node: {node.kind.name}"
To demonstrate how the transpiler works, let's create a simple astx
AST and transpile it to Python code.
Suppose you have the following astx
AST representing a simple Python function:
# example_ast.py
from astx.base import SourceLocation
from astx.literals import LiteralInt32, LiteralString
from astx.variables import Variable, VariableAssignment
from astx.expressions import BinaryOp
from astx.blocks import Block
from astx.functions import FunctionDef
from astx.types import Int32
from astx.enums import EncodingKind
# Define function arguments
class Argument:
"""Placeholder for the Argument class."""
def __init__(self, name: str, type_: TypeExpr):
self.name = name
self.type_ = type_
class Arguments:
"""Placeholder for the Arguments class."""
def __init__(self, args):
self.args = args
# Define return statement
class ReturnStmt:
"""Placeholder for the ReturnStmt class."""
def __init__(self, value, loc: SourceLocation = SourceLocation(line=0, col=0)):
self.value = value
self.loc = loc
self.kind = ASTKind.ReturnStmtKind
# Function parameters
args = Arguments(args=[
Argument(name="x", type_=Int32()),
Argument(name="y", type_=Int32())
])
# Function body
body = Block(nodes=[
VariableAssignment(
target=Variable(name="result"),
value=BinaryOp(
op_code="+",
lhs=Variable(name="x"),
rhs=Variable(name="y"),
loc=SourceLocation(line=2, col=8)
),
loc=SourceLocation(line=2, col=4)
),
ReturnStmt(
value=Variable(name="result"),
loc=SourceLocation(line=3, col=4)
)
])
# Function definition
add_function = FunctionDef(
name="add",
args=args,
body=body,
returns=Int32(),
decorators=[],
loc=SourceLocation(line=1, col=0)
)
Note: The above example_ast.py
includes placeholder classes (Argument
, Arguments
, ReturnStmt
) to simulate an astx
AST. You should replace these placeholders with actual implementations from your astx
module.
Create a new script named generate_code.py
to transpile the example AST:
# generate_code.py
from example_ast import add_function
from astx2python import ASTxToPythonGenerator
# Initialize the generator
generator = ASTxToPythonGenerator()
# Generate Python code
python_code = generator.generate(add_function)
print(python_code)
Execute the transpiler script:
python generate_code.py
Expected Output:
def add(x, y) -> int:
result = (x + y)
return result
While the above implementation serves as a smoke test, you can enhance it further to handle more complex AST nodes and language features.
Implement visitor functions for other AST node types as needed. For example:
@dispatch(ASTxToPythonGenerator, IfStmt)
def visit(generator: ASTxToPythonGenerator, node: IfStmt) -> str:
"""Handle IfStmt nodes."""
condition = generator.generate(node.condition)
header = f"if {condition}:"
body = generator._generate_block(node.body)
orelse = ""
if node.orelse:
orelse_header = f"else:"
orelse_body = generator._generate_block(node.orelse)
orelse = f"\n{generator.indent_str * generator.indent_level}{orelse_header}\n{orelse_body}"
return f"{header}\n{body}{orelse}"
Extend the transpiler to support classes, loops, exception handling, etc., by implementing corresponding visitor functions.
Ensure that nested blocks and proper indentation are consistently handled to generate syntactically correct Python code.
Implement robust error handling to catch and report unsupported or malformed AST nodes gracefully.
@dispatch(ASTxToPythonGenerator, ASTNodes)
def visit(generator: ASTxToPythonGenerator, node: ASTNodes) -> str:
"""Handle unsupported or generic ASTNodes."""
return f"# Unsupported AST node: {node.kind.name}"
Ensure that your transpiler's visitor functions align closely with the structure and hierarchy of your astx
AST nodes. This alignment facilitates easier maintenance and extension.
As your transpiler grows, consider organizing visitor functions into separate modules or classes based on functionality (e.g., expressions, statements, types) to enhance code organization.
Develop a suite of unit tests covering various AST node types and language constructs to validate the correctness of the transpiler.
Maintain clear documentation for each visitor function, outlining its purpose and the AST node types it handles. This practice aids future development and onboarding.
plum
FeaturesExplore additional features of Plum, such as type annotations and fallback mechanisms, to enhance the flexibility and robustness of your transpiler.
By integrating Plum's multiple dispatch into your ASTxToPythonGenerator
, you've created a flexible and scalable transpiler framework. This setup not only simplifies the handling of diverse AST node types but also lays the groundwork for expanding the transpiler to support more complex language features in the future.
from gpt:
1. Overview of the Transpiler Design
Visitor Pattern Approach
A common and effective way to traverse and translate ASTs is by using the Visitor Pattern. In this pattern, you create a visitor class that has specific methods to handle each type of AST node. This approach allows for clean separation between the AST structure and the code generation logic.
Key Components
astx
classes representing different language constructs (e.g., literals, binary operations, function definitions).2. Implementing the Transpiler
File Structure
For simplicity, we'll create a single Python module named
astx2python.py
containing the transpiler logic.2.1. Import Necessary Classes
Ensure that
astx2python.py
can access the necessaryastx
classes. Adjust the import paths based on your project structure.2.2. Define the Generator Class
Create the
ASTxToPythonGenerator
class with methods to handle different AST node types.2.3. Implement Visitor Methods
Below are example visitor methods for various AST node types. You can expand these methods to handle more node types as your AST evolves.
2.3.1. Literals
2.3.2. Variables and Assignments
2.3.3. Binary and Unary Operations
2.3.4. Function Definitions
2.3.5. Control Flow Statements
2.3.6. Expressions
2.3.7. Additional Helper Methods
You may need additional helper methods to handle other node types or specific scenarios. Below is an example of handling
TypeAliasStmt
and handling indentation.2.4. Handling Indentation
Proper indentation is crucial for Python code. The
_generate_block
method (already included in function definitions) manages indentation levels.2.5. Example Usage of the Transpiler
Below is an example of how to use the
ASTxToPythonGenerator
to transpile a simpleastx
AST to Python code.2.5.1. Creating an Example AST
2.5.2. Transpiling the AST to Python Code
2.5.3. Expected Output
Running
generate_code.py
should output:3. Enhancing the Transpiler
3.1. Handling More AST Node Types
To make the transpiler more robust, implement visitor methods for additional AST node types as needed. Refer to your
astx
classes and ensure that each node type has a corresponding visitor method inASTxToPythonGenerator
.3.2. Managing Complex Structures
For more complex language features like classes, exception handling, or asynchronous programming, expand the generator with appropriate visitor methods. Ensure that the generated Python code maintains correct syntax and semantics.
3.3. Error Handling
Implement error handling within the generator to gracefully handle unsupported or unexpected AST node types. This can involve raising exceptions or logging warnings.
3.4. Testing and Validation
Create a suite of unit tests to verify that various ASTx nodes are correctly transpiled into Python code. This ensures that your transpiler behaves as expected and helps catch any regressions during development.
4. Final Notes
Scalability: While this transpiler serves as a smoke test, consider modularizing the generator by separating visitor methods into different mixins or base classes as the AST grows in complexity.
Extensibility: The current design allows easy addition of new node types. Simply add new visitor methods following the naming convention
visit_<ASTKind>
.Code Generation Enhancements: For more sophisticated code generation, such as handling scope, managing variable declarations, or optimizing the output code, you may need to incorporate additional logic into the generator.
Integration with Other Tools: This transpiler can serve as a foundation for integrating with other compiler phases, such as semantic analysis or optimization.
By following this structured approach, you can develop a simple yet effective transpiler from your
astx
AST to Python code. This not only serves as a valuable testing tool but also lays the groundwork for more advanced code generation capabilities in the future.