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How can I handle eval() exec() multiline as first in first out

I have code from this Question: Why is Python’s eval() rejecting this multiline string, and how can I fix it?

def multiline_eval(expr, context={}):
    "Evaluate several lines of input, returning the result of the last line"
    tree = ast.parse(expr)
    eval_exprs = []
    exec_exprs = []
    for module in tree.body:
        if isinstance(module, ast.Expr):
            eval_exprs.append(module.value)
        else:
            exec_exprs.append(module)
    exec_expr = ast.Module(exec_exprs, type_ignores=[])
    exec(compile(exec_expr, 'file', 'exec'), context)
    results = []
    for eval_expr in eval_exprs:
        results.append(eval(compile(ast.Expression((eval_expr)), 'file', 'eval'), context))
    return 'n'.join([str(r) for r in results])

When I use this code:

multiline_eval('''
print("Hello World1")

for a in range(5):
    print(a)
print("Hello World2")
''')

The result is:

0
1
2
3
4
Hello World1
Hello World2

I am expecting this:

Hello World1
0
1
2
3
4
Hello World2

How can I change the code? I tried to change the code, but I was not successful.

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Answer

The code you’ve posted sorts the ast tree body in 2 buckets, the ast.Exprs and the rest, and then processes them bucket-wise. So, you have to remove the “bucketing”. You could try something like the following:

import ast

def multiline_eval(expr, ctx={}):
    results = []
    for node in ast.parse(expr).body:
        if isinstance(node, ast.Expr):
            result = eval(compile(ast.Expression(node.value), '<string>', 'eval'), ctx)
            results.append(result)            
        else:
            module = ast.Module([node], type_ignores=[])
            results.append(exec(compile(module, '<string>', 'exec'), ctx))
    return 'n'.join(map(str, results))
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