Wolfram Language & System 11.0 (2016)|Legacy Documentation

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is an option for EmbedCode that gives rules specifying the mapping to external types in an embedded code.


  • ExternalTypeSignature->{{"var1"->"type1",},"rettype"} specifies that vari should be of external type typei, and that the return type for the whole function should be rettype.
  • ExternalTypeSignature->{{"type1","type2",},"rettype"} takes the n^(th) argument to be of type typen.
  • The typei are native types specified as they are named in the target language.
  • In many languages, possible external types include: "int", "double", "string".
  • The types of arguments can often be inferred from other data in APIFunction etc. where they appear. A type of Automatic will use the inferred form.
  • In languages where types are used, the return type typically has to be set explicitly.
  • ExternalTypeSignature->"rettype" specifies the return type, and if possible infers all argument types.
  • In languages with dynamic typing, or without types, types do not usually have to be set.

ExamplesExamplesopen allclose all

Basic Examples  (1)Basic Examples  (1)

Create a cloud object:

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Generate a complete Java file to call the cloud object that can be pasted into a Java project:

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The types of arguments can often be deduced automatically. The return type must be specified explicitly:

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Introduced in 2014