Boo

Issues with using nullable types in Boo

Details

  • Type: Bug Bug
  • Status: Resolved Resolved
  • Priority: Major Major
  • Resolution: Fixed
  • Affects Version/s: None
  • Fix Version/s: 0.8.2
  • Component/s: Compiler
  • Labels:
    None
  • Number of attachments :
    0

Description

Two issues:

nullable types in Boo don't support implicit casting
nullable types HasValue occasionally flips out.

booish output below:

>>> testVar = Nullable[of long]()
>>> testVar = 3 #int
--------------^
ERROR: Cannot convert 'int' to 'System.Nullable`1[[System.Int64, mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089]]'.
>>> testVar = 3L #long
3
>>> testVar =

{'1' : DBNull.Value }

['1'] #assign null value

>>> testVar.HasValue
System.InvalidCastException: Specified cast is not valid.
at Input25Module.Main(String[] argv)
>>> testVar = 4L
4
>>> testVar.HasValue
true
>>>

Issue Links

is depended upon by

Task - A task that needs to be done. BOO-822 Interpretator incorrectly adds two nullable decimals

  • Major - Major loss of function.
  • Resolved - A resolution has been taken, and it is awaiting verification by reporter. From here issues are either reopened, or are closed.
is related to

Improvement - An improvement or enhancement to an existing feature or task. BOO-820 Honor generic parameter constraints when constructing generic types

  • Minor - Minor loss of function, or other problem where easy workaround is present.
  • Resolved - A resolution has been taken, and it is awaiting verification by reporter. From here issues are either reopened, or are closed.
is superceded by

Improvement - An improvement or enhancement to an existing feature or task. BOO-985 Allow arithmetic operations with nullables

  • Minor - Minor loss of function, or other problem where easy workaround is present.
  • Resolved - A resolution has been taken, and it is awaiting verification by reporter. From here issues are either reopened, or are closed.
relates to

Bug - A problem which impairs or prevents the functions of the product. BOO-805 Can't use == on nullable types

  • Major - Major loss of function.
  • Resolved - A resolution has been taken, and it is awaiting verification by reporter. From here issues are either reopened, or are closed.

Activity

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Cedric Vivier added a comment -

Third issue is that the compiler does not generate an error when declaring "x as Nullable of string" or other non-valuetype.

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Cedric Vivier added a comment - Third issue is that the compiler does not generate an error when declaring "x as Nullable of string" or other non-valuetype.
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Cedric Vivier added a comment -

For later reference here's the message used by gmcs :
error CS0453: The type `string' must be a non-nullable value type in order to use it as type parameter `T' in the generic type or method `System.Nullable<T>'.

Show
Cedric Vivier added a comment - For later reference here's the message used by gmcs : error CS0453: The type `string' must be a non-nullable value type in order to use it as type parameter `T' in the generic type or method `System.Nullable<T>'.
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Avishay Lavie added a comment -

(re: third issue) that's because current generics support doesn't validate that generic parameters satisfy their constraints. Generic parameter constraints will be added, I assume, when doing BOO-763, since they're mostly relevant when declaring generic type definitions rather than when constructing types.
I'll add an issue to represent this.

Show
Avishay Lavie added a comment - (re: third issue) that's because current generics support doesn't validate that generic parameters satisfy their constraints. Generic parameter constraints will be added, I assume, when doing BOO-763 , since they're mostly relevant when declaring generic type definitions rather than when constructing types. I'll add an issue to represent this.
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Cedric Vivier added a comment -

fixed in rev 2898

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Cedric Vivier added a comment - fixed in rev 2898

People

  • Assignee:
    Cedric Vivier
    Reporter:
    Arron Washington
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Dates

  • Created:
    Updated:
    Resolved: