Difference between revisions of "EDT:EGL Language Part Types"

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| <br>
 
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| bgcolor="#cccccc" | ''Record''<br>
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| bgcolor="#cccccc" | ''Record<sup>6</sup>''<br>
 
| <br>done
 
| <br>done
 
| [https://bugs.eclipse.org/bugs/show_bug.cgi?id=352045 JS:Record]<br>
 
| [https://bugs.eclipse.org/bugs/show_bug.cgi?id=352045 JS:Record]<br>
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#<span style="background: rgb(255,165,0)">There are no called programs in EDT. Use libraries for "local calls" and services for "remote calls".</span>  
 
#<span style="background: rgb(255,165,0)">There are no called programs in EDT. Use libraries for "local calls" and services for "remote calls".</span>  
 
#<span style="background: rgb(255,165,0)">We intend to support function overloading in all implementations, even JavaScript.</span>  
 
#<span style="background: rgb(255,165,0)">We intend to support function overloading in all implementations, even JavaScript.</span>  
#<span style="background: rgb(255,165,0)">Nullability means that a variable may really be null. It's not an "I'm null" flag like in RBD. A NullValueException will be thrown if you try to access a field or function of a null variable, even a record. A NullValueException will be thrown if a null variable is an operand to a math operator, an array access, a substring access, a comparison, or a bitwise operator.</span> The string concatenation operators will work the same as in RBD with respect to nulls. &nbsp;:: treats null as the empty string, and&nbsp;?: results in null if either operand is null. <span style="background: rgb(255,165,0)">A question mark won't be allowed on the second operand of the AS and ISA operators (the name of the type).</span>
+
#Records are value types, so record variables may be declared with a question mark following the name of the type to indicate that they're nullable. <span style="background: rgb(255,165,0)">Nullability means that a variable may really be null. It's not an "I'm null" flag like in RBD. A NullValueException will be thrown if you try to access a field or function of a null variable, even a record. A NullValueException will be thrown if a null variable is an operand to a math operator, an array access, a substring access, a comparison, or a bitwise operator.</span> The string concatenation operators will work the same as in RBD with respect to nulls. &nbsp;:: treats null as the empty string, and&nbsp;?: results in null if either operand is null. <span style="background: rgb(255,165,0)">A question mark won't be allowed on the second operand of the AS and ISA operators (the name of the type).</span>

Revision as of 14:28, 19 July 2011

Please see the parent of this page, EDT:EGL Language.

Part Types (Table 1)

Part Types Core JavaScript Java Debug
DataItem1
2d
JS: DataItem


Function2, 5
done
JS: Function overloading


Top-level function2, 5
done



Delegate2
done
JS:Delegates


Record6

done
JS:Record


Structured Record

done
N/S N/S N/S
ExternalType

done
JS:ExternalType


Handler

1d
JS:Handler


Library

done
done


Service

1d



Interface3

done



Enumeration

JS: Enumeration


Program4

done
N/S


Array




Nullability6




DataTable

done
N/S N/S N/S
Form

done
N/S N/S N/S

Notes on Table 1

  1. In RBD a DataItem can only be used for primitive types. In EDT it can be used for any type.
  2. See also Table 2: Function Parameters.
  3. Interfaces can be implemented by services and handlers (every kind of "logic part" which can be instantiated).
  4. There are no called programs in EDT. Use libraries for "local calls" and services for "remote calls".
  5. We intend to support function overloading in all implementations, even JavaScript.
  6. Records are value types, so record variables may be declared with a question mark following the name of the type to indicate that they're nullable. Nullability means that a variable may really be null. It's not an "I'm null" flag like in RBD. A NullValueException will be thrown if you try to access a field or function of a null variable, even a record. A NullValueException will be thrown if a null variable is an operand to a math operator, an array access, a substring access, a comparison, or a bitwise operator. The string concatenation operators will work the same as in RBD with respect to nulls.  :: treats null as the empty string, and ?: results in null if either operand is null. A question mark won't be allowed on the second operand of the AS and ISA operators (the name of the type).