diff options
Diffstat (limited to 'doc/syntax/exceptions.rdoc')
| -rw-r--r-- | doc/syntax/exceptions.rdoc | 19 |
1 files changed, 15 insertions, 4 deletions
diff --git a/doc/syntax/exceptions.rdoc b/doc/syntax/exceptions.rdoc index a2e75616fb..cdf9d367a7 100644 --- a/doc/syntax/exceptions.rdoc +++ b/doc/syntax/exceptions.rdoc @@ -17,7 +17,14 @@ wish to limit the scope of rescued exceptions: # ... end -The same is true for a +class+ or +module+. +The same is true for a +class+, +module+, and +block+: + + [0, 1, 2].map do |i| + 10 / i + rescue ZeroDivisionError + nil + end + #=> [nil, 10, 5] You can assign the exception to a local variable by using <tt>=> variable_name</tt> at the end of the +rescue+ line: @@ -79,7 +86,7 @@ To always run some code whether an exception was raised or not, use +ensure+: rescue # ... ensure - # this always runs + # this always runs BUT does not implicitly return the last evaluated statement. end You may also run some code when an exception is not raised: @@ -89,7 +96,11 @@ You may also run some code when an exception is not raised: rescue # ... else - # this runs only when no exception was raised + # this runs only when no exception was raised AND return the last evaluated statement ensure - # ... + # this always runs. + # It is evaluated after the evaluation of either the `rescue` or the `else` block. + # It will not return implicitly. end + +NB : Without explicit +return+ in the +ensure+ block, +begin+/+end+ block will return the last evaluated statement before entering in the +ensure+ block. |