Project

General

Profile

Actions

Bug #20308

closed

`it` and numbered parameters do not work in `eval`

Added by kddnewton (Kevin Newton) 8 months ago. Updated 8 months ago.

Status:
Closed
Assignee:
-
Target version:
-
[ruby-core:116969]

Description

I am not sure if this is a purposeful restriction or not, so I apologize if this is not a "bug" per se.

Currently if you use it or _1 (numbered parameters) in eval they do not work with compile.c:

irb(main):001> 1.tap { eval("_1") }
(eval):1:in `block in <top (required)>': undefined local variable or method `_1' for main:Object (NameError)
Did you mean?  _

They work accidentally with prism because I didn't know this wasn't allowed. Is it a bug? Or is this on purpose?


Related issues 1 (0 open1 closed)

Is duplicate of Ruby master - Bug #18837: Not possible to evaluate expression with numbered parameters in itRejectedActions

Updated by matheusrich (Matheus Richard) 8 months ago

Interesting behavior. I'd expect that to work since other "kinds of arguments" work:

def foo(*)
  eval "puts(*)"
end

def foo(**)
  eval "puts(**)"
end

def foo(...)
  eval "puts(...)"
end

Updated by jeremyevans0 (Jeremy Evans) 8 months ago

My understanding is the parse.y behavior is expected, because use of _1/it inside the block changes the block's arity:

lambda{it}.arity
# => 1
lambda{eval('it')}.arity
# => 0

So if we supported eval('it') in non-lambda procs, it would make support inconsistent with lambda procs.

Updated by alanwu (Alan Wu) 8 months ago ยท Edited

Looks like it's a known limitation and discussed before in #18837.

Updated by kddnewton (Kevin Newton) 8 months ago

Ahh! Thank you @jeremyevans0 (Jeremy Evans) and @alanwu (Alan Wu) I knew there must have been a reason. I'll close this.

Actions #5

Updated by kddnewton (Kevin Newton) 8 months ago

  • Status changed from Open to Closed
Actions #6

Updated by nobu (Nobuyoshi Nakada) 8 months ago

  • Is duplicate of Bug #18837: Not possible to evaluate expression with numbered parameters in it added
Actions

Also available in: Atom PDF

Like0
Like0Like0Like0Like0Like0Like0