I've made a mistake and forgot to specify keyword arguments in defgeneric the first time I've compiled it. Now I really don't want to restart SLIME only to redefine this one defgeneric to include more arguments. Is there a way to "undefine" it somehow?
Oh, sorry, never mind, after removing all methods defined for that generic, SBCL redefined it, so it's all good now:
(remove-method #'some-generic
(find-method #'some-generic '() (list of method types)))
For posterity.
See fmakunbound.
(fmakunbound 'some-generic)
SLIME has the command Ctrl-c Ctrl-u to undefine a function. Set the cursor on the function symbol and then type the sequence.
Another possibility would be to compile one or more methods with the additional arguments and then, after your Common Lisp implementation "complains" about the unknown parameters, select the restart which updates the arguments available in the generic function.
Related
I have 2 destructs: monster & orc. The orc includes monster. The generic monster has generic defmethods on it named monster-show & monster-hit. The orc has a specialized monster-hit but still keeps the generic monster-show. My problem is that I accidentally named the specialized method for the orc the wrong name (monster-show), so now when I try to use the generic monster-show, it runs code that it shouldn't (the wrongly named defmethod I compiled) instead of running the generic method.
Is there a way to get rid of a specialized defmethod in Slime + SBCL?
If you don't have an IDE or such, you can use remove-method:
(remove-method #'monster-show
(find-method #'monster-show
()
(list (find-class 'orc))))
Here’s how I would do it using the slime inspector:
Enter the generic function you want to modify:
CL-USER> #'monster-show
#<GENERIC FUNCTION: MONSTER-SHOW>
Move your cursor on to it and inspect the object by typing C-c C-v TAB
The inspector should show a list of methods for the function identified by their specialisers. Navigate to one and press the button to remove/unbind the method. You can click for this too.
Also by the description of your hierarchy it would probably be wiser to use real classes and not structs. Structs tens not to give a particularly big speedup compared to classes.
On spacemacs w/ evil mode :slime-inspect RET #'monster-show. Select remove-method on the orc.
I am using Emacs with SLIME for my development environment. When I type (write-to and then C-M-i I get the following autocompletions:
Click on a completion to select it.
In this buffer, type RET to select the completion near point.
Possible completions are:
write-to-sting
write-to-string
I know Common Lisp is powerful, but I guess write-to-sting is not in the ANSI standard. Google didn't offer a single hit for this function. Then I tried to find it in the SBCL code, but alas
(documentation 'write-to-sting 'function) returns nil so it doesn't have a documentation string.
When I try to execute the function (write-to-sting) I get The function COMMON-LISP-USER::WRITE-TO-STING is undefined.
Apropos also finds an unbound function:
(apropos 'write-to)
WRITE-TO
WRITE-TO-STING
WRITE-TO-STRING (fbound)
My question is: What is going on? Does anyone knows the story behind this function?
At some point during your interaction with the Lisp environment, you wrote write-to-sting and it was read by the Lisp reader. The symbol was interned in the COMMON-LISP-USER package. After all, maybe you intended to implement a function that sends an email to Sting, who knows?
Auto-completion works by filtering the currently known symbols in the environment.
You can safely (unintern 'write-to-sting) (or implement it).
This is probably a newbie question... but is it possible to show the definition of a (user defined) function? While debugging/optimizing it is convenient to quickly see how a certain function was programmed.
Thanks in advance.
You can use the #edit macro, which is supposed to take you to the definition of a method, similarly to how the #which macro which shows the file and line # where that particular method was defined, for example:
julia> #which push!(CDFBuf(),"foo")
push!{T<:CDF.CDFBuf}(buff::T, x) at /d/base/DA/DA.jl:105
julia> #which search("foobar","foo")
search(s::AbstractString, t::AbstractString) at strings/search.jl:146
Note that methods that are part of Julia will show a path relative to the julia source directory "base".
While this is not an automatic feature available with Julia in general (as pointed out by Stefan), if you add docstrings when you define your initial function, you can always use the help?> prompt to query this docstring. For example
julia> """mytestfunction(a::Int, b)""" function mytestfunction(a::Int, b)
return true
This attaches the docstring "mytestfunction(a::Int, b)" to the function mytestfunction(a::Int, b). Once this is defined, you can then use the Julia help prompt (by typing ? at the REPL), to query this documentation.
help?> mytestfunction
mytestfunction(a::Int, b)
Lisp is said to enable redefinitions of its core functions.
I want to define an alias to the function cl:documentation function, such that
(doc 'write 'function) === (documentation 'write 'function)
How can this be done and made permanent in SBCL?
Creating an Alias
You are not trying to redefine (i.e., change the definition of) the system function documentation, you want to define your own function with a shorter name which would do the same thing as the system function.
This can be done using fdefinition:
(setf (fdefinition 'doc) #'documentation)
How to make your change "permanent" in common lisp
There is no standard way, different implementation may do it differently, but, generally speaking, there are two common ways.
Add code to an init file - for beginners and casual users
SBCL
CLISP
Clozure
ECL
The code in question will be evaluated anew every time lisp starts.
Pro:
Easy to modify (just edit file)
Takes little disk space
Normal lisp invocation captures the change
Con:
Evaluated every time you start lisp (so, slows start up time if the code is slow)
Save image - for heavy-weight professionals
SBCL
CLISP
Clozure
ECL - not supported
The modified lisp world is saved to disk.
Pro:
Start uptime is unaffected
Con:
Requires re-dumping the world on each change
Lisp image is usually a large file (>10MB)
Must specify the image at invocation time
Even though #sds has already answered pretty thoroughly I just wanted to add that the utility library serapeum has defalias
I use a simple macro for this:
(defmacro alias (to fn)
`(setf (fdefinition ',to) #',fn))
e.g.
(alias neg -) => #<Compiled-function ... >
(neg 10) => -10
Other answers include detail about how to make this permanent.
I've been banging my head against ASDF2 and just want a sanity check. When I eval (asdf:initialize-source-registry) with no arguments or with any argument, I get no value. When I check source-registry, I get an empty hash table. Is this a bug?
I'm on AllegroCL Enterprise 64-bit on Windows 7.
This sounds mostly correct to me. In my SBCL init file, I have:
(pushnew #p"/home/paulnath/.asdf/" asdf:*central-registry* :test #'equal)
(push #p"/home/paulnath/.asdf/" asdf:*central-registry*)
Check section 7.9 in the ASDF manual.
Checking the source of asdf.lisp, the source path ends with a (values), which of course returns no values. So I expect to not return anything.
Old question, but yes, that behavior is correct.
If you provide an argument to asdf::initialize-source-registry, then asdf::source-registry will (probably, you may have no .asd files...) not be empty. Also note that lisp distributions may put their own stuff into asdf::source-registry. For example, SBCL puts its internals into it.
The answer given doesn't really answer the question, as asdf::central-registry is a different (and supposedly deprecated even though it takes precedence over asdf::source-registry) mechanism.