Functions to test for truthy and falsey values

[infused-kim]

Hi,

I came up with another small idea to make just EVEN MORE amazing... :)

I ran across the following use-case:

# Run init_server playbook (ask for pass if last arg is true or 1)
[group("playbooks")]
server_init host_pattern ask_pass="false":
    ansible-playbook playbooks/server/init_server.yml --limit {{ host_pattern }} {{ if ask_pass != "false" { "--ask-pass" } else { "" } }} {{ extra_args }}

I wanted to have an argument that lets me do just server_init foobar true or just server_init foobar yes or just server_init foobar 1.

Essentially, I think it would be great to have the ability to test for truthy values like this:

# Run init_server playbook 
[group("playbooks")]
server_init host_pattern ask_pass="false":
    ansible-playbook playbooks/server/init_server.yml --limit {{ host_pattern }} {{ if is_truthy(ask_pass) { "--ask-pass" } else { "" } }} {{ extra_args }}

And whether the user writes yes, 1, true, TRUE, it would return true.

[casey]

I can definitely see how this would be useful.

However, it doesn't save a whole lot of typing. Instead of doing foo != "false", you do is_truthy(foo), which is a little better, but obscures what's going on.

Also, for backwards compatibility reasons, we couldn't change what was considered truthy, so if we wanted to add, for example, YES to the set, we couldn't.

So I'm not sure if this is worth it 🤔

[infused-kim]

I totally understand. But the idea is to not require the user to type or remember to type “false” as an argument. Instead the user can write no, 0, false, etc.

Ideally, it would lower() the input string and then do the comparison so that capitals don’t matter.

[laniakea64]

whether the user writes yes, 1, true, TRUE, it would return true.

This can easily and more flexibly be achieved with existing features:

truthy_regex := '(?i)^(?:yes|1|true)$'

# Run init_server playbook (ask for pass if last arg is true or 1)
[group("playbooks")]
server_init host_pattern ask_pass="false":
    ansible-playbook playbooks/server/init_server.yml --limit {{ host_pattern }} {{ if ask_pass =~ truthy_regex { "--ask-pass" } else { "" } }} {{ extra_args }}

[infused-kim]

This is awesome and totally solves the problem.

Thank you!

[casey]

Ooo, nice one @laniakea64.