phate6660 / bcalc Goto Github PK

First of all thanks for implementing PEMDAS. 🏆 It was great to see you implement it that fast.

I did some testing:

$ ./bcalc '(2+2)*2'
2
$ ./bcalc '2*(2+2)'
26
$ ./bcalc '2^(2+2)'
26
$ ./bcalc '(2+2)^2'
3
$ ./bcalc '(2)^2'
1
$ ./bcalc '2+2+2^2'
8

All of these are wrong. Am I doing anything wrong?

Right now it formats the output by default, something like 2,000,000,000. But I was hoping if an arg could be added to disable this and just output the result as is.

It is kind of related to #8 . But wanted to keep it separate.

Just wanted to think for some use cases. So thought it would be great to have it. No hurry for these.

We usually have to test ourselves when we have new features to see if that broke any old features. What if we had tests to do that automatically for us?

Found out that bats is a good testing system for bash. I have some tests written for it in a branch here.

I'll push a PR shortly for your consideration, but I was thinking if bats is even too much for this project. I mean, if it can be done with pure bash only that would be awesome in a way.

I've implemented bcalc into my config and it's working great for me. Recently I started to support FreeBSD as an alternate platform. Then I noticed something.

The current shebang line used in bcalc and test is:

#!/bin/bash

This is fine on GNU+Linux systems. But BSD systems such as FreeBSD and others store the bash binary in /usr/local/bin/bash, so it fails there saying /bin/bash: bad interpreter: No such file or directory. One way to fix this is to direct to bash through env, like this:

#!/usr/bin/env bash

Here is an article about why env should be included in shebang. There are discussions around the web whether this is needed. But general idea is that this is suggested if the script is intended to be portable. So I think this change should make it usable in more platforms.

I was thinking about the default comma formatting. Right now it does this:

$ ./bcalc '2*1000000000'
2,000,000,000

But there are other countries with other number formatting traditions. For example I found this article showing some of them. It would be great if this formatting can be specified.

I'm not sure what would be the best way to do it. I was hoping if it was possible to specify the format with an arg like ###,###,###.##. Another way would probably be to mention the country codes.

Congratulations on crossing off so many TODOs!

I've checked the readme and it has some commands on debugging:

$ ./bcalc [100]-[50]
final_array = [ 1 0 0 ] - [ 5 0 ]
number_array = 100 50
operation_array = -
calculation = 100-50
50

But when I execute the same, it gives me:

$ ./bcalc [100]-[50]
50

Maybe there are some parameters missing?

Thanks for creating the project.

First, I tried:

$ ./bcalc '1+1'
2
$ ./bcalc '(1+1)*2'
12
$ ./bcalc '2*(1+1)'
13

The last 2 are wrong. Then I found Support operating on more than two numbers on the TODO list. I think it's better to show an error message that more than 2 numbers are not supported, rather than showing wrong results. Some users could be really confused, like me! :)

It's up to you, but I think adding basic instructions on the README.md on how to use it would be nice. Plus some examples, some limitations (e.g. #1) in the readme would make it more user friendly and show what it's capable of before downloading it.