Is it a good idea to list imported symbols explicitly?

[kamichal]

Please help me in deciding if that change I made on #20 is correct.
It was a huge PR and it sneaked somewhere in between before I asked this question.
Test that exposes it is here:

prophy/prophyc/tests/generators/test_python.py

Lines 10 to 40 in 775ef4b

	def test_includes_rendering():
	common_include = model.Include("foo", [
	model.Constant("symbol_1", 1),
	model.Constant("number_12", 12),
	])
	nodes = [
	common_include,
	model.Include("root/ni_knights", [
	model.Include("../root/rabbit", [
	common_include,
	model.Constant("pi", "3.14159"),
	model.Typedef("definition", "things", "r32", "docstring"),
	]),
	model.Constant("symbol_2", 2),
	]),
	model.Include("../root/baz_bar", []),
	model.Include("many/numbers", [model.Constant("number_%s" % n, n) for n in reversed(range(20))]),
	]
	ref = """\
	from foo import number_12, symbol_1
	from ni_knights import definition, pi, symbol_2
	from numbers import (
	number_0, number_1, number_10, number_11, number_13, number_14, number_15,
	number_16, number_17, number_18, number_19, number_2, number_3, number_4,
	number_5, number_6, number_7, number_8, number_9
	)
	"""
	# call twice to check if 'duplication avoidance' machinery in _PythonTranslator.translate_include works ok
	assert serialize(nodes) == ref
	assert serialize(nodes) == ref

Before that change python generator created such a import statement:

from foo import *
from ni_knights import *
from numbers import *

Now the imported symbols are listed explicitly. The list contains everything that is defined by this Include and each sub-Include element unless it's already imported by previous statements in this file.

from foo import number_12, symbol_1
from ni_knights import definition, pi, symbol_2
from numbers import (
    number_0, number_1, number_10, number_11, number_13, number_14, number_15,
    number_16, number_17, number_18, number_19, number_2, number_3, number_4,
    number_5, number_6, number_7, number_8, number_9
)

There is also some "duplication avoidance" mechanism that raises my doubts at most.
The code responsible for that generation is here:

prophy/prophyc/generators/python.py

Lines 63 to 78 in 775ef4b

	def translate_include(self, include):
	included = list(sorted(n.name for n in include.defined_symbols() if n.name not in self.included_symbols))
	self.included_symbols.update(included)
	if not included:
	return ""
	statement_begin = "from %s import " % include.name.split("/")[-1]
	symbols = ", ".join(included)
	if len(statement_begin) + len(symbols) <= 80:
	return statement_begin + symbols
	@import_breaker
	def importer():
	yield symbols
	return "%s(\n%s)" % (statement_begin, "".join(importer()))

Please let me know if you would like to bring it back to the original form.

[aurzenligl]

Explicit listing allows to figure out which symbol is imported from which include -> not a bad thing to know. Unless there are problems stemming from being explicit - I see no problems with it.