groovy

Unhelpful error message re parameters to functions

Details

  • Type: Improvement Improvement
  • Status: Closed Closed
  • Priority: Minor Minor
  • Resolution: Won't Fix
  • Affects Version/s: 2.0-beta-3
  • Fix Version/s: None
  • Component/s: Compiler
  • Labels:
    None
  • Environment:
    Debian Unstable, OpenJDK 7, Groovy master/HEAD
  • Number of attachments :
    0

Description

The script:

def theMessage ( a , b = ' ' , c , d = '.' ) {
  a + b + c + d
}

println theMessage ( 'Hello' )

results in the error message:

groovy.lang.MissingMethodException: No signature of method: ConsoleScript0.theMessage() is applicable for argument types: (java.lang.String) values: [Hello]
Possible solutions: theMessage(java.lang.Object, java.lang.Object), theMessage(java.lang.Object, java.lang.Object, java.lang.Object), theMessage(java.lang.Object, java.lang.Object, java.lang.Object, java.lang.Object)
at org.codehaus.groovy.runtime.ScriptBytecodeAdapter.unwrap(ScriptBytecodeAdapter.java:55)
at org.codehaus.groovy.runtime.callsite.PogoMetaClassSite.callCurrent(PogoMetaClassSite.java:78)
at org.codehaus.groovy.runtime.callsite.CallSiteArray.defaultCallCurrent(CallSiteArray.java:49)
at org.codehaus.groovy.runtime.callsite.AbstractCallSite.callCurrent(AbstractCallSite.java:133)
at org.codehaus.groovy.runtime.callsite.AbstractCallSite.callCurrent(AbstractCallSite.java:141)
at ConsoleScript0.run(ConsoleScript0:5)
...

which is understandable, and not incorrect, but isn't perhaps as helpfully user oriented as perhaps it could be.

Activity

Ascending order - Click to sort in descending order
Hide
Permalink
Paul King added a comment - - edited

Do you have a suggestion for what you might like to have seen for this case? Is your main point that giving the options where defaults values could be used just adds noise?

Show
Paul King added a comment - - edited Do you have a suggestion for what you might like to have seen for this case? Is your main point that giving the options where defaults values could be used just adds noise?
Hide
Permalink
blackdrag blackdrag added a comment -

Russel, we currently can't think of a better error message. I close the issue until someone (mostly you) has any idea. Feel free to reopen the issue then

Show
blackdrag blackdrag added a comment - Russel, we currently can't think of a better error message. I close the issue until someone (mostly you) has any idea. Feel free to reopen the issue then
Hide
Permalink
Russel Winder added a comment -

I have been trying hard to think of how Groovy can do a better job, but the semantics of Groovy combined with the parsing strategy don't actually leave a lot of room for manoeuvre. Probably best to mark this as "Won't Fix", rather than "Incomplete".

On the positive side mayhap put some examples of this sort of thing somewhere on the Web so that the error message gets into the Google index referring to an explanation of the point about how defaulted parameters get handled. The page on this is fine per se but doesn't mention error handling, just when things go right.

Show
Russel Winder added a comment - I have been trying hard to think of how Groovy can do a better job, but the semantics of Groovy combined with the parsing strategy don't actually leave a lot of room for manoeuvre. Probably best to mark this as "Won't Fix", rather than "Incomplete". On the positive side mayhap put some examples of this sort of thing somewhere on the Web so that the error message gets into the Google index referring to an explanation of the point about how defaulted parameters get handled. The page on this is fine per se but doesn't mention error handling, just when things go right.

People

  • Assignee:
    blackdrag blackdrag
    Reporter:
    Russel Winder
Vote (0)
Watch (1)

Dates

  • Created:
    Updated:
    Resolved: