Bug #10778: `defined?(expr)` should be equivalent to `defined? (expr)` not `(defined? expr)`

• Status: Rejected
• Assignee: -
• Target version: -
• ruby -v: ruby 2.2.0p0 (2014-12-25 revision 49005) [x86_64-linux]
• Backport: 2.0.0: UNKNOWN, 2.1: UNKNOWN, 2.2: UNKNOWN

[bughit (bug hit)]

defined? is an operator not a method, its operand is defined as the expressions to its right.

It does not even require a space: defined?a

So defined?(a) should be equivalent to defined? (a) instead of (defined? a)

[nobu (Nobuyoshi Nakada)]

• Status changed from Open to Feedback
• Priority changed from Normal to 3

[jeremyevans0 (Jeremy Evans)]

There isn't a description of the actual problem caused by this behavior, but I'm guessing, it is something like this:

defined? a && defined? b # defined?(a && defined? b)
# => "expression"

defined? (a) && defined? (b) # defined?((a) && defined? (b))
# => "expression"

defined?(a) && defined?(b) # (defined?(a)) && (defined?(b))
# => nil

I'm reasonably confident changing the last example to be parsed as the first two examples would break existing code and would go against the expectations of most Ruby programmers.

[nobu (Nobuyoshi Nakada)]

• Status changed from Feedback to Rejected

In Ruby, a space before an opening parenthesis often has significant meanings.
Combining defined?(a) higher than && is considered reasonable.