[Enhancement] New Option for Help, Initial Module, and Tests for the Source Code Documentation

[kevinmatthes]

Hello, @wert007,

This Pull Request introduces the following new features:

• a "help" option, as many CLIs have them,
• an initial module in order to enhance the maintainability of the application, and
• some initial source code documentation strings ("docstrings") for cargo doc.

This Pull Request is also intended to discuss the source code style in order to agree on some initial contribution guidelines.

[kevinmatthes]

At the moment, the project consists of a single monolithic source file which might require additional effort to maintain the source code. Hence, I decided to outsource the features to dedicated modules. Together with the intended source code documentation, as discussed in #5, this procedure keeps the code better readable.

I decided to begin with the usage function since there was a small typo in its call. This issue was addressed by hard coding the application's name into the respective function because it is assumed to not being changed at runtime. Furthermore, due the removal of a single println ! () call, some small performance benefits were achieved.

[wert007]

Okay, before I start dissecting your pull request: Please run cargo fmt to auto format the code.

Secondly run cargo clippy which will lint your code to be up to rust standards. And follow the recommendations. 😄

[kevinmatthes]

Okay, I applied your suggestions. Please note that the linter still complains about 6 regions which I do not edited with none of my commits.

I order to do not modify the behaviour of the application unintendedly, I would prefer to leave them as they are, at the moment.

[kevinmatthes]

Mostly, the complaints concern the closures of .map_err. Once, the member merge: Option <String> is considered obsolete.

[wert007]

Added some feedback here 😄

[wert007]

Okay, I applied your suggestions. Please note that the linter still complains about 6 regions which I do not edited with none of my commits.

I order to do not modify the behaviour of the application unintendedly, I would prefer to leave them as they are, at the moment.

Yeah I saw that. I will fix these after the pull request merged I think 😅

[wert007]

Great! 😄

[kevinmatthes]

I just found out the solutions to the linter warnings. I am going to submit them to this Pull Request.

[kevinmatthes]

The sole open linter warning concerns the unused merge member.

[wert007]

Thanks, I merged it. And will now look at the unused merge field. 😄