Bug #21381: Different error messages when mixing `it` and `_1` in block for Prism and parse.y

• Status: Closed
• Assignee: nobu (Nobuyoshi Nakada)
• Target version: -
• ruby -v: ruby 3.4.4 (2025-05-14 revision a38531fd3f) +PRISM [x86_64-linux] and ruby 3.4.4 (2025-05-14 revision a38531fd3f) [x86_64-linux]
• Backport: 3.2: UNKNOWN, 3.3: UNKNOWN, 3.4: UNKNOWN

[herwin (Herwin W)]

$ ruby -v -e 'proc { it + _1 }'
ruby 3.4.4 (2025-05-14 revision a38531fd3f) +PRISM [x86_64-linux]
-e: -e:1: syntax error found (SyntaxError)
> 1 | proc { it + _1 }
    |             ^~ numbered parameters are not allowed when 'it' is already used

$ ruby -v --parser=parse.y -e 'proc { it + _1 }'
ruby 3.4.4 (2025-05-14 revision a38531fd3f) [x86_64-linux]
-e:1: 'it' is already used in
-e:1: current block here
proc { it + _1 }
ruby: compile error (SyntaxError)

and the other way around:

$ ruby -v -e 'proc { _1 + it}'
ruby 3.4.4 (2025-05-14 revision a38531fd3f) +PRISM [x86_64-linux]
-e: -e:1: syntax error found (SyntaxError)
> 1 | proc { _1 + it}
    |             ^~ `it` is not allowed when a numbered parameter is already used

$ ruby -v --parser=parse.y -e 'proc { _1 + it}'
ruby 3.4.4 (2025-05-14 revision a38531fd3f) [x86_64-linux]
-e:1: numbered parameter is already used in
-e:1: current block here
proc { _1 + it}
ruby: compile error (SyntaxError)

It would expect the relevant part of messages to match. To be clear, I would consider this the relevant parts:

numbered parameters are not allowed when 'it' is already used
'it' is already used in

and

`it` is not allowed when a numbered parameter is already used
numbered parameter is already used

[herwin (Herwin W)]

(very minor issue, I wouldn't mind too much if it would not be fixed)

[mame (Yusuke Endoh)]

• Assignee set to nobu (Nobuyoshi Nakada)

[nobu (Nobuyoshi Nakada)]

• Status changed from Open to Closed

Applied in changeset git|0e0008da0f19d098a2e98902f2215c126aca0101.

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[Bug #21381] Refine error messages for it and numbered parameters