Databases
StackOverflow2013
Postsdbo
PO
 

Note that there are some explanatory texts on larger screens.

plurals
  1. PO
    primarykey
    data
    text
    <p>I guess a solution could be only imprecise because of lack of static typing rules.</p> <p>I'm not aware of some tool that checks exceptions, but you could come up with your own tool matching your needs (a good chance to play a little with static analysis).</p> <p>As a first attempt, you could write a function that builds an AST, finds all <code>Raise</code> nodes, and then tries to figure out common patterns of raising exceptions (e. g. calling a constructor directly)</p> <p>Let <code>x</code> be the following program:</p> <pre><code>x = '''\ if f(x): raise IOError(errno.ENOENT, 'not found') else: e = g(x) raise e ''' </code></pre> <p>Build the AST using the <code>compiler</code> package:</p> <pre><code>tree = compiler.parse(x) </code></pre> <p>Then define a <code>Raise</code> visitor class:</p> <pre><code>class RaiseVisitor(object): def __init__(self): self.nodes = [] def visitRaise(self, n): self.nodes.append(n) </code></pre> <p>And walk the AST collecting <code>Raise</code> nodes:</p> <pre><code>v = RaiseVisitor() compiler.walk(tree, v) &gt;&gt;&gt; print v.nodes [ Raise( CallFunc( Name('IOError'), [Getattr(Name('errno'), 'ENOENT'), Const('not found')], None, None), None, None), Raise(Name('e'), None, None), ] </code></pre> <p>You may continue by resolving symbols using compiler symbol tables, analyzing data dependencies, etc. Or you may just deduce, that <code>CallFunc(Name('IOError'), ...)</code> "should definitely mean raising <code>IOError</code>", which is quite OK for quick practical results :)</p>
    singulars
    1. This table or related slice is empty.
    1. POPython: How can I know which exceptions might be thrown from a method call
      singulars
      1. PTQuestion
    1. PTAnswer
    1. USAndrey Vlasovskikh
    1. USAndrey Vlasovskikh
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. POPython: How can I know which exceptions might be thrown from a method call
      singulars
      1. PTQuestion
    1. This table or related slice is empty.
    1. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTUpMod
    2. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTAcceptedByOriginator
    3. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTUpMod
    1. COThanks for this interesting answer. Didn't understand though why should I look for something more other than all the raise nodes. Why should I "resolving symbols using compiler symbol tables, analyzing data dependencies"? Isn't the only way to raise exception is by raise() ?
      singulars
      1. PO
      1. USGabiMe
    2. COGiven the `v.nodes` value above, you cannot actually say, what the thing is `Name('IOError')` or `Name('e')`. You don't know what value(s) those `IOError` and `e` can point to, as they are so-called free variables. Even if their binding context were known (here symbol tables come into play), you should perform some kind of data dependency analysis to infer their exact values (this should be hard in Python).
      singulars
      1. PO
      1. USAndrey Vlasovskikh
    3. COAs you are looking for a practical semi-automated solution, a list of `['IOError(errno.ENOENT, "not found")', 'e']` displayed to the user is just fine. But you cannot infer actual classes of values of variables represented by strings :) (sorry for reposting)
      singulars
      1. PO
      1. USAndrey Vlasovskikh
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload