begin
raise 'alert'
rescue => e
p "Error"
end
=> Error
Everything is fine here, But look at another case,begin
require 'IamNotThere'
rescue => e
p "Error"
end
=> LoadError: no such file to load -- IamNotThere
Never expected ?, Our rescue block didn't handle this case.begin
require 'IamNotThere'
rescue Exception=> e
p "Error"
end
=> Error
Again, everything is safe here.So, It's always better narrow down our expectation or use 'Exception => e'. Default is 'StandardError'.
Heirarchy:
Exception
NoMemoryError
ScriptError
LoadError
NotImplementedError
SyntaxError
SignalException
Interrupt
StandardError
ArgumentError
IOError
EOFError
IndexError
LocalJumpError
NameError
NoMethodError
RangeError
FloatDomainError
RegexpError
RuntimeError
SecurityError
SystemCallError
SystemStackError
ThreadError
TypeError
ZeroDivisionError
SystemExit
fatal
