Exit codes

Every command ends with an exit code. A plain call exits 0 whenever it answers, whether the answer is yes, no or not sure; --check makes the answer itself the exit code.

echo 'Where is my parcel?' |
  thinkthen decide --check \
    'Does the customer request a refund?'

Output

false
Copy

No: the message asks about a delivery, so --check exits 1. The answer still prints, so a person can read it.

Every exit code

Code	When
0	The command answered. With --check, the answer was yes.
1	With --check, the answer was no.
2	An argument, option or setting is wrong or missing, such as an unset key or an empty text. Nothing was asked.
3	With --check, the answer was not sure.
4	The model service failed, or it failed for every line, as with a wrong key.
5	A file couldn't be read or written, or a toolbox couldn't be read.
6	One or more lines failed. The others still hold their answers.
130	You pressed Ctrl-C. A second Ctrl-C exits at once.
141	The program reading the output, such as head, closed early.

A failed line wins over every --check answer, so 6 beats 0, 1 and 3.

Which functions take --check

Function	0	1	3
decide	yes	no	not sure
choose	a choice		not sure
find	a line was found	no line answers	not sure
filter	at least one line kept	none kept	none kept, and one was not sure

decide, choose and find take one text with --check, from a pipe, --text or one file. filter takes any number of lines. Each function's page shows --check at work, starting with decide.

Where errors go

Answers go to standard output and errors go to standard error, so a pipe carries only answers. Here the file doesn't exist, so nothing is printed, the error goes to standard error, and the command exits 5:

thinkthen decide 'Does the customer request a refund?' \
  no-such-file.txt

Output

(an empty line)

Copy

thinkthen: local.io: input no-such-file.txt could not be opened
Copy

Each error is one line: thinkthen:, a code such as local.io, then what went wrong. When one line of many fails, the error also names its position, its id and its file. Troubleshooting lists each code and its fix.

Branch on the code in a script

case sends each answer its own way. > /dev/null hides the printed answer, because the script reads the code instead.

echo 'I was charged twice for one invoice.' |
  thinkthen decide --check --low 0.2 --high 0.8 \
    'Does the customer request a refund?' > /dev/null
status=$?
case "$status" in
  0) echo 'send to the refunds queue' ;;
  1) echo 'send to the inbox' ;;
  3) echo 'send to a person' ;;
  *) echo 'stop: read the error above'
     exit "$status" ;;
esac

Output

send to a person
Copy

The double charge falls between the bars of 0.2 and 0.8, so decide exits 3 and the message goes to a person. The last line catches every other code, such as 2 or 6, so a broken call never passes as a no.

Next

Toolboxes saves your questions in a file.