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Why isn't the following working? (Yes, I am working with 2.9.0final and turned the "-Xexperimental" option on.)
implicit def any2Dynamic(a: Any) = new Dynamic {
def applyDynamic(name: String)(args: Any*) = {
println(a + name)
}
}
"Say".hello // value hello is not a member of java.lang.String
One can argue about how meaningful this is... If this would work as expected what precedence will take place at "Say".toInt: StringLike.toInt or (new Dynamic {...}).applyDynamic("toInt")?
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10.2.An implicit dynamic conversion exists from an expression of type dynamic to any type T .
An implicit conversion sequence is the sequence of conversions required to convert an argument in a function call to the type of the corresponding parameter in a function declaration. The compiler tries to determine an implicit conversion sequence for each argument.
An implicit cast is a cast that the database server can invoke automatically when it encounters data types that cannot be compared with built-in casts. This type of cast enables the database server to automatically handle conversions between other data types.
In C# 4.0, a new type is introduced that is known as a dynamic type. It is used to avoid the compile-time type checking. The compiler does not check the type of the dynamic type variable at compile time, instead of this, the compiler gets the type at the run time.
The compiler first looks for an implicit view from String => { def hello: ? }. That fails, so it then checks if String <: Dynamic. These are not combined.
This dynamic apply feature has not been finalized -- in Scala 2.9.0 it is experimental, and subject to change. But I doubt this would be included, as with such an implicit, you throw all type safety out the window. You would never get a compile error for misspelled method names or incorrect argument types. What is your use case?
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