Custom error or not

[Cecil Westerhof]

I am using a function to get a default database so I do not have to
work with configuration files. Something like:
proc ::dcblUtilities::getDefaultDB {{key ""} {DB db} {timeoutSecs 10} \
{configDB ~/.tcl.sqlite}} {
When the key is empty, I use the scriptname as key.

When no key can be retrieved, I give an error:
error "Cannot retrieve database for ${key}"

But what is the tcl way when something goes wrong with opening the
database(s): let the error propagate, or catching the error and
throwing my own error?

--
Cecil Westerhof
Senior Software Engineer
LinkedIn: http://www.linkedin.com/in/cecilwesterhof

[Gerald Lester]

On 02/01/2018 06:21 AM, Cecil Westerhof wrote:
> I am using a function to get a default database so I do not have to
> work with configuration files. Something like:
> proc ::dcblUtilities::getDefaultDB {{key ""} {DB db} {timeoutSecs 10} \
> {configDB ~/.tcl.sqlite}} {
> When the key is empty, I use the scriptname as key.
>
> When no key can be retrieved, I give an error:
> error "Cannot retrieve database for ${key}"
>
> But what is the tcl way when something goes wrong with opening the
> database(s): let the error propagate, or catching the error and
> throwing my own error?

Either way -- it depends on what you will think is clearer to the person
using your code.

--
+----------------------------------------------------------------------+
| Gerald W. Lester, President, KNG Consulting LLC |
| Email: Gerald...@kng-consulting.net |
+----------------------------------------------------------------------+

[Cecil Westerhof]

Gerald Lester <Gerald...@KnG-Consulting.net> writes:

> On 02/01/2018 06:21 AM, Cecil Westerhof wrote:
>> I am using a function to get a default database so I do not have to
>> work with configuration files. Something like:
>> proc ::dcblUtilities::getDefaultDB {{key ""} {DB db} {timeoutSecs 10} \
>> {configDB ~/.tcl.sqlite}} {
>> When the key is empty, I use the scriptname as key.
>>
>> When no key can be retrieved, I give an error:
>> error "Cannot retrieve database for ${key}"
>>
>> But what is the tcl way when something goes wrong with opening the
>> database(s): let the error propagate, or catching the error and
>> throwing my own error?
>
> Either way -- it depends on what you will think is clearer to the person
> using your code.

That you do not know when writing a public package. (I am going to
publish it on GitHub.) But I think that I will catch and throw my own
error.

[Gerald Lester]

A public package -- in that case I agree it should furnish its own error
if it is an "expected" or known issue.