hammertime

An interactive error console similar to those found in Lisp and Smalltalk environments.

Synopsis

Simply require the Hammertime library:

    require 'hammertime'

    $broken = true

    def faulty_method
      raise "Oh no!" if $broken
    end

    3.times do |n|
      puts "Attempt (#{n+1}/3)"
      begin
        faulty_method
        puts "No error raised"
      rescue => error
        puts "Error raised: #{error.inspect}"
      end
    end

When an error is raised, a menu of possible actions will be presented at the console:

    === Stop! Hammertime. ===
    An error has occurred at example.rb:4:in `raise_runtime_error'
    The error is: #<RuntimeError: Oh no!>
    1. Continue (process the exception normally)
    2. Ignore (proceed without raising an exception)
    3. Permit by type (don't ask about future errors of this type)
    4. Permit by line (don't ask about future errors raised from this point)
    5. Backtrace (show the call stack leading up to the error)
    6. Debug (start a debugger)
    7. Console (start an IRB session)
    What now?

This enables a fix-and-continue style of development:

    $ ruby example.rb
    Attempt (1/3)

    === Stop! Hammertime. ===
    An error has occurred at example.rb:6:in `faulty_method'
    The error is: #<RuntimeError: Oh no!>
    1. Continue (process the exception normally)
    2. Ignore (proceed without raising an exception)
    3. Permit by type (don't ask about future errors of this type)
    4. Permit by line (don't ask about future errors raised from this point)
    5. Backtrace (show the call stack leading up to the error)
    6. Debug (start a debugger)
    7. Console (start an IRB session)
    What now?
    7

    >> $broken = false
    => false
    >> exit

    1. Continue (process the exception normally)
    2. Ignore (proceed without raising an exception)
    3. Permit by type (don't ask about future errors of this type)
    4. Permit by line (don't ask about future errors raised from this point)
    5. Backtrace (show the call stack leading up to the error)
    6. Debug (start a debugger)
    7. Console (start an IRB session)
    What now?
    2
    No error raised
    Attempt (2/3)
    No error raised
    Attempt (3/3)
    No error raised

Known Bugs

• Hammertime cannot intercept exceptions which are raised from native code.

TODO

• Better integration with IRB to enable a "Retry" option.
• Start console/debugger at fail site, instead of in Hammertime code.
• Tests

Copyright

Copyright © 2010 Avdi Grimm. See LICENSE for details.