[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
bug#6497: documentation `indirect-function', `symbol-function' do not en
bug#6497: documentation `indirect-function', `symbol-function' do not enumerate return value type
Tue, 22 Jun 2010 19:42:57 -0400
documentation of function `indirect-function' and `symbol-function' do
not adequately enumerate all of the types of return values (nor does
it even make mention of them) and docstring of `indirect-function' too
closeley mirrors that of `indirect-variable'.
Additionally, the value of its argument OBJECT does not reflect that
of the `symbol-function' arg SYMBOL it should because its return value
more closely resembles that of `symbol-function' than
,---- (documentation 'indirect-variable)
| Return the variable at the end of OBJECT's variable chain.
| If OBJECT is a symbol, follow all variable indirections and return the
| final variable. If OBJECT is not a symbol, just return it. Signal a
| cyclic-variable-indirection error if there is a loop in the variable
| chain of symbols.
| (fn OBJECT)
,---- (documentation 'indirect-function)
| Return the function at the end of OBJECT's function chain.
| If OBJECT is not a symbol, just return it. Otherwise, follow all
| function indirections to find the final function binding and return
| it. If the final symbol in the chain is unbound, signal a
| void-function error. Optional arg NOERROR non-nil means to return nil
| instead of signalling. Signal a cyclic-function-indirection error if
| there is a loop in the function chain of symbols.
| (fn OBJECT &optional NOERROR)
,---- (documentation 'symbol-function)
| Return SYMBOL's function definition. Error if that is void.
| (fn SYMBOL)
Given the similarity of docstrings for `indirect-variable' and
`indirect-function' it is possible for a user to assume the quoting
rules of `indirect-variable' apply as well to `indirect-function'.
In the following example `indirect-variable' returns regardless of
whether the arg OBJECT is quoted:
Whereas, in the following evaluation of `indirect-function' the first
use of an arg as unquoted symbol signals an error.
This problem isn't an issue were it not for the close resemblance of
the `indirect-function' `indirect-variable' docstrings.
More troublesome though is that neither `indirect-function' nor
`symbol-function' document their return values in any meaningful way:
Following is an attempt at fleshing out those return values not
specified by the existing docstrings (substitute OBJECT for SYMBOL
| If OBJECT satisfies the predicate `subrp' return an unreadable
| object of the form:
| #<subr SOME-SUBR-NAME>
| If OBJECT is an "autuload object" type its return value is a list of
| values suitable for use as arguments to the `autoload' function and
| of the form:
| (autoload "<FILENAME>" <DOCSTRING-POSN> <INTERACTIVE> <TYPE>)
| Note, the <TYPE> element for OBJECT's return value as "autoload
| object" is nil for a function and `macro' or `t' for a macro.
| If value of OBJECT is a "byte-code function" type, e.g. it would
| satisfy the predicate `byte-code-function-p', and OBJECT is not a
| "Lisp macro" its value is returned as an unreadable vector of the
| #[ ... ]
| if OBJECT is a "Lisp macro" in it value is returned as a cons of the
| (macro . #[ ... ])
|[Prev in Thread]
||[Next in Thread]|
- bug#6497: documentation `indirect-function', `symbol-function' do not enumerate return value type,
MON KEY <=