Low setup usage

[jayvdb]

Some alternatives to moban have simplicity on their side.

It should be possible for moban to be easily used in an ad-hoc manner without a config file , like moban foo.jj2 to generate foo using environment variables.

c.f. https://github.com/andreasjansson/envtpl/blob/master/README.md

Or if there is a config file, moban foo.jj2 would load it and generate foo or the target listed in the config if it is present there.

[chfw]

yep, can easily do that.

The reason why it hasn't been done is missing actual use case.

[chfw]

@jayvdb @CLiu13 , previously I suggested to inject env to globals. Now, I got another suggestion:

Referencing https://github.com/andreasjansson/envtpl/blob/master/README.md, I think we could do a bit better in the following way:

1. incorporate environment variables as a base data config for all data config files, meaning each data config automatically overrides the environment variable.

for example, scenario 1:

env var:

export HELLO="TEST"

test.jj2:
{{HELLO}}

moban -t test.jj2

shall simply get

TEST

scenario 2:

env var:

export HELLO="TEST"

data.yml

HELLO: world

test.jj2:
{{HELLO}}

moban -t test.jj2

shall simply get

world

2. we may extend our functionality to support

moban -t "{{HELLO}}"

and get moban.output

#149

[chfw]

hmm.. after checking the implementation, item 1 is there :)