net.wf.scan(false) fails on every second call

[Mynogs]

If I call net.wf.scan(false) on the console input it fails with this message:

stdin:1: 134217730:general fail
stack traceback:
[C]: in field 'scan'
stdin:1: in main chunk
[C]: in ?

Next time it works. Then it fails. Then it works and so on.
Greetings

[ar055]

This not errors, see WIKI
if table is true: a Lua table with the scan's result, or an exception.
Use Exception handling

[Mynogs]

Where is this behavior documented in the wiki? The description for net.wf.scan is only a few lines long. I don't find anything there.

I entered net.wf.scan(false) in the console. Therefore true and not false as parameters. Exception handling is for a Lua program, not for the console. I know that.
Greetings