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digitalmars.D - Weird behavior with getopt for invalid user input

reply Andrew Pennebaker <andrew.pennebaker gmail.com> writes:
In many getopt implementations, the -h/--help banner is printed 
when the user supplies invalid arguments. However, D's getopt 
instead throws an exception, printing a stack trace and confusing 
some non-technical users.

That's okay, we can catch GetoptException and try to print the 
usage information instead. But that also doesn't work so well, as 
the getopt spec cannot bind to a variable when an exception is 
thrown. Again, other getopt implementations tend to separate the 
getopt spec object construction from argument validation into 
separate function calls, which gives the programmer more 
flexibility for how to handle any errors.

Sigh, when I manually `defaultGetoptPrinter(format("Usage: %s 
[OPTIONS]", program), opts.options);`, I think I can do this by 
typing out the getopt spec a second time, overriding the args 
with ["-h"]. But this is starting to require a ridiculous number 
of hacks, when getopt could have just executed -h on error, as 
many users would expect.
Dec 08 2018
next sibling parent Andrew Pennebaker <andrew.pennebaker gmail.com> writes:
On Saturday, 8 December 2018 at 19:48:24 UTC, Andrew Pennebaker 
wrote:

 In many getopt implementations, the -h/--help banner is printed 
 when the user supplies invalid arguments. However, D's getopt 
 instead throws an exception, printing a stack trace and 
 confusing some non-technical users.

 That's okay, we can catch GetoptException and try to print the 
 usage information instead. But that also doesn't work so well, 
 as the getopt spec cannot bind to a variable when an exception 
 is thrown. Again, other getopt implementations tend to separate 
 the getopt spec object construction from argument validation 
 into separate function calls, which gives the programmer more 
 flexibility for how to handle any errors.

 Sigh, when I manually `defaultGetoptPrinter(format("Usage: %s 
 [OPTIONS]", program), opts.options);`, I think I can do this by 
 typing out the getopt spec a second time, overriding the args 
 with ["-h"]. But this is starting to require a ridiculous 
 number of hacks, when getopt could have just executed -h on 
 error, as many users would expect.


Posted a workaround:

https://forum.dlang.org/post/kfupjcpsovzcxwaifyst forum.dlang.org
Dec 08 2018
prev sibling parent zabruk <sorry noem.ail> writes:
https://issues.dlang.org/show_bug.cgi?id=14525
Reported: 2015-04-29
Dec 09 2018