Global command `#` for commenting

General
1

I am somewhat ashamed to admit that I repeatedly used the # character to comment out lines of my buspirate scripts. Ok, technically, these are just text files on the host that I copy/paste from… I’m not using the scripting functionality yet). Of course, that doesn’t comment out the line like I hope…

since the # character is the command to reset the buspirate :rofl:.

This began my search for way to enable scripts (and other command-line input) to have inline comments. I think this could also help with the documentation screencasts, such as having the chapter headers also shown as typed-in comments, as the chapter headings are not always clearly visible in the documentation playback.

Review of common programming language options:

Generally, it should avoid conflicting with the first character of any existing valid commands. This excludes the following characters:

  • aAbcdfFgGhilLmopPrstvVwW0-9@#$^(-_.:=~[]{}"/\
  • zZ if added as global command to transition to HiZ mode
Not available

  • Ada style -- … bus syntax conflict (data high)
  • AppleScript (* … script selection conflict
  • C++ // … bus syntax conflict (clock high)
  • C /* .... */ … bus syntax conflict (clock high)
  • Haskell {- ... -} … bus syntax conflict (start 2)
  • Java /** .... */ … bus syntax conflict (clock high)
  • Java // … bus syntax conflict (clock high)
  • LUA --[[ ... ]]-- … bus syntax conflict (data high)
  • Nim # … resets the buspirate
  • Objective-C // … bus syntax conflict (clock high)
  • OCaml (* … script selection conflict (and nesting)
  • Pascal (* … script selection conflict (and nesting)
  • Perl # … resets the buspirate
  • PHP # … resets the buspirate
  • Python # … resets the buspirate
  • R # … resets the buspirate
  • Ruby # … resets the buspirate
  • Ruby =begin … numeric conversion conflict
  • SQL -- … bus syntax conflict (data high)
  • Swift // … bus syntax conflict (clock high)
Available

  • ColdFusion, XML, HTML each use <!--- ... --!>
    • but > is already used
    • might imply multi-line comment support (non-goal)
  • Fortran C
    • but lowercase c conflicts, so undesirable because it would mean case-sensitive commenting
    • also, Fortran knowledge is less common
  • MATLAB %
    • While % is not currently used, may want to keep this for future expansion of bus syntax?
  • BASIC and Windows command scripts rem
    • Conflicts with r bus syntax
    • But already have rm (storage) command … so possible?
    • Broadly understood to comment a single line

Recommendation

I thus propose that rem be added as a global command.

UPDATE: Ian approved changing # to be named reboot, which will allow # to comment out the remaining line of input.

The rem new # command might log the line (e.g., to log files and/or debugger), and is generally for documentation purposes only … no functional effects should rely on this command.

Thoughts?

1 Like
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How about we change the command to reset? The single character command is a legacy of Bus Pirate v3.x, which wasn’t really capable of parsing multiple character commands.

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Are you suggesting to change # to be a the comment command?

That is a very common way to mark a line as a comment.

If so, I fully support changing # to be a line comment, and adding reset as a new command. :tada:

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4

I think it’s a fair change, but I refuse to do it before the docs update is done :wink:

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5

I seem to recall that one of the BP3 firmware builds included a BASIC interpreter as part of the language/

Crazy talk here… Or future idea…

If the syntax was modified so that each line would start with a number (or to be more precise, no existing command starts with a number and a space) , then it would be possible in the future to have the “number space” prefix tell the BP to store the instruction in memory without execution.

Add a few more commands, ala the BASIC interpreter, the LIST, LOAD and SAVE commands,and the REM command and bingo - you have the ability to edit and document scripts directly on the BP.

The REM command would fit nicely with this idea.

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6

Neat idea but conflicts already with buspirate scripts, which allow numbers.

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7

Excuse my memory, but which command starts with a number and a space?

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8

I stand corrected. I didn’t see any requirement for there to be something that prevents this, but … I suppose it does:

I2C> [ 0x6C ]

I2C START
TX: 0x6C ACK
I2C STOP
I2C> [ 108 ]

I2C START
TX: 108 ACK
I2C STOP
I2C> 108
Invalid command: 108. Type ? for help.

I had thought this would send the byte across via I2C without requiring a start / stop bit. Hm…

1 Like
9

The first half of this change is now PR 242:

Rename # to be reboot

1 Like
10

Thank you for the pull request. It is now in main. Docs have been updated to match.

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