18.1.3 Queries on AST Objects

Two functions are provided which allow an application to determine if an AST was created as an expression or a suite. Neither of these functions can be used to determine if an AST was created from source code via expr() or suite() or from a parse tree via sequence2ast().

isexpr(ast): When ast represents an 'eval' form, this function returns true, otherwise it returns false. This is useful, since code objects normally cannot be queried for this information using existing built-in functions. Note that the code objects created by compileast() cannot be queried like this either, and are identical to those created by the built-in compile() function.

issuite(ast): This function mirrors isexpr() in that it reports whether an AST object represents an 'exec' form, commonly known as a ``suite.'' It is not safe to assume that this function is equivalent to "not isexpr(ast)", as additional syntactic fragments may be supported in the future.

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