Bug #6086

Number of arguments and named parameters

Added by marcandre (Marc-Andre Lafortune) about 6 years ago. Updated almost 6 years ago.

Target version:


While working on the messages of "wrong number of arguments" error (see #6085), I realized that the new named parameter feature can lead to misleading error messages:

def foo(x: 42)

arg = {x: :bar}
foo(arg) # => nil (no error)
arg = :bar
foo(arg) # => ArgumentError: wrong number of arguments (1 for 0)

It would be better if the wording was changed for methods accepting options. Maybe something like:

foo(arg) # => ArgumentError: wrong number of arguments (1 for 0 **)


Related issues

Related to Ruby trunk - Bug #6085: Treatment of Wrong Number of ArgumentsClosed2012-02-25
Related to Ruby trunk - Feature #5474: keyword argumentClosed2011-10-23


#1 Updated by ko1 (Koichi Sasada) about 6 years ago

  • Assignee set to mame (Yusuke Endoh)

#2 Updated by shyouhei (Shyouhei Urabe) about 6 years ago

  • Status changed from Open to Assigned

#3 Updated by mame (Yusuke Endoh) about 6 years ago

  • Assignee changed from mame (Yusuke Endoh) to matz (Yukihiro Matsumoto)

Matz, what do you think?

I'm not against this. But I'm not sure how surprising this behavior is,
until I encounter it in actual use case.
"(1 for 0 **)" is not very good-looking, but I have no alternative idea.

Yusuke Endoh

#4 [ruby-core:46432] Updated by matz (Yukihiro Matsumoto) almost 6 years ago

  • Status changed from Assigned to Rejected

Even though I understand the point, I am against the expression "(1 for 0 **)".
So until some one come up with better expression, we leave this as it is now.


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