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2020-11-16
14:19 Closed ticket [d22ad20205]: "dict unset d key subkey" fails if key does not exist plus 5 other changes artifact: 69d5a81801 user: oehhar
14:19 Ticket [d22ad20205]: 4 changes artifact: 393f75ecb9 user: oehhar
2018-07-02
11:04 Ticket [d22ad20205]: 3 changes artifact: 110ef0dbb8 user: sebres
11:03 Ticket [d22ad20205]: 3 changes artifact: 823f434d5a user: sebres
10:24 New ticket [d22ad20205]. artifact: 87f9039ad3 user: oehhar

Ticket UUID: d22ad202055093292992c6aea053188f8b3d4abe
Title: "dict unset d key subkey" fails if key does not exist
Type: Bug Version: >= 8.5
Submitter: oehhar Created on: 2018-07-02 10:24:28
Subsystem: 15. Dict Object Assigned To: nobody
Priority: 5 Medium Severity: Minor
Status: Closed Last Modified: 2020-11-16 14:19:43
Resolution: Fixed Closed By: oehhar
    Closed on: 2020-11-16 14:19:43
Description:

If a dictionary key is unset, there is no error, if it does not exist:

% set d {}
% dict unset d a

There is an error raised, if a key on the path of the subkey does not exist:

% set d {}
% dict unset d a b
key "a" not known in dictionary

IMHO this is inconsistent and should not rise an error.

At least the documentation should write about error behaviour.


I can understand, that an error is raised, if the (sub)dict is not a valid dict.

% set d {1}
% dict unset d a
missing value to go with key
% set d {a 1}
% dict unset d a b
missing value to go with key

User Comments: oehhar added on 2020-11-16 14:19:30:

Tested again with tcl8.6.10. Is fixed. Thank you, Harald


sebres added on 2018-07-02 11:03:13:

Still worse (as regards the inconsistency), it does not produce any error if dictionary self (variable) does not exists:

% unset -nocomplain d
% catch { dict unset d a }
0

So I'm agree with Harald's conclusion, the `dict unset` must not produce an error if sub-key does not exists also.