Language::LispPerl - A lisp in pure Perl with perl bindings.
use Language::LispPerl::Evaler;
my $lisp = Language::LispPerl::Evaler->new();
# Load core functions and macros
$lisp->load("core.clp");
my $res = $lisp->eval(q|
(defmacro defn [name args & body]
`(def ~name
(fn ~args ~@body)))
(defn foo [arg]
(println arg))
(foo "hello world!") ;comment here
|);
# $res is the last lisp object evaluated.
Language::LispPerl is a pure Perl lisp interpreter. It is a fork of CljPerl that focuses on making embedding lisp code in your Perl written software straightforward.
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From version 0.004
This uses Moose instead of Moo. This should not have any impact on your code, except if you have written your own role for 'Language::LispPerl::BuiltIns'. It will need to be a Moose::Role instead of a Moo::Role.
Here is how to bind to your own Perl functions from lisp.
This assumes that your perl functions live in My::App::LispFunctions
package My::App::LispFunctions;
sub do_stuff {
my ($x , $y ) = @_;
..
return;
}
sub say_stuff {
my ($x , $y ) = @_;
..
return $string_or_number;
}
sub is_stuff {
..
# Note that here we return a raw lisp object.
return Language::LispPerl->true();
}
;; These lisp binding functions will live
;; in the namespace 'myapp'
;; Note that you need core.clp to be loaded in the Evaler.
(ns myapp
(. require My::App::LispFunctions)
(defn do-stuff [x y]
(.My::App::LispFunctions do_stuff ^{:return "nil"} x y ))
(defn say-stuff [x y]
(.My::App::LispFunctions say_stuff ^{:return "scalar"} x y ))
(defn is-stuff [x y]
(.My::App::LispFunctions is_stuff ^{:return "raw"} x y)))
( require "myapp.clp" ) ;; Or in Perl $lisp->load("myapp.clp");
( myapp#do-stuff .. .. ) ;; Note the myapp# namespace marker.
(. require AnyEvent)
(def cv (->AnyEvent condvar))
(def count 0)
(def t (->AnyEvent timer
{:after 1
:interval 1
:cb (fn [ & args]
(println count)
(set! count (+ count 1))
(if (>= count 10)
(set! t nil)))}))
(.AnyEvent::CondVar::Base recv cv)
.TBC.
* Reader forms
* Symbols :
foo, foo#bar
* Literals
* Strings :
"foo", "\"foo\tbar\n\""
* Numbers :
1, -2, 2.5
* Booleans :
true, false . Or from Perl: Language::LispPerl->true() and Language::LispPerl->false()
* Nil :
nil . Or from Perl: Language::LispPerl->nil();
* Keywords :
:foo
* Lists :
(foo bar)
* Vectors :
[foo bar]
* Maps :
{:key1 value1 :key2 value2 "key3" value3}
* Quote ('). :
'(foo bar)
* Comment (;) :
; comment
* Dispatch (#) :
* Accessor (:) :
#:0 ; index accessor
#:"key" ; key accessor
#::key ; key accessor
* Sender (!) :
#!"foo"
* XML ([) :
#[body ^{:attr "value"}]
* Metadata (^) :
^{:key value}
* Syntax-quote (`) :
`(foo bar)
* Unquote (~) :
`(foo ~bar)
* Unquote-slicing (~@) :
`(foo ~@bar)
* list :
(list 'a 'b 'c) ;=> '(a b c)
* car :
(car '(a b c)) ;=> 'a
* cdr :
(cdr '(a b c)) ;=> '(b c)
* cons :
(cons 'a '(b c)) ;=> '(a b c)
* key accessor :
(#::a {:a 'a :b 'a}) ;=> 'a
* keys :
(keys {:a 'a :b 'b}) ;=> (:a :b)
* index accessor :
(#:1 ['a 'b 'c]) ;=> 'b
* sender :
(#:"foo" ['a 'b 'c]) ;=> (foo ['a 'b 'c])
* xml :
#[html ^{:class "markdown"} #[body "helleworld"]]
* length :
(length '(a b c)) ;=> 3
(length ['a 'b 'c]) ;=> 3
(length "abc") ;=> 3
* append :
(append '(a b) '(c d)) ;=> '(a b c d)
(append ['a 'b] ['c 'd]) ;=> ['a 'b 'c 'd]
(append "ab" "cd") ;=> "abcd"
* type :
(type "abc") ;=> "string"
(type :abc) ;=> "keyword"
(type {}) ;=> "map"
* meta :
(meta foo ^{:m 'b})
(meta foo) ;=> {:m 'b}
* fn :
(fn [arg & args]
(println 'a))
* apply :
(apply list '(a b c)) ;=> '(a b c)
* eval :
(eval "(+ 1 2)")
* require :
(require "core")
* def :
(def foo "bar")
(def ^{:k v} foo "bar")
* set! :
(set! foo "bar")
* let :
(let [a 1
b a]
(println b))
* defmacro :
(defmacro foo [arg & args]
`(println ~arg)
`(list ~@args))
* if :
(if (> 1 0)
(println true)
(println false))
(if true
(println true))
* while :
(while true
(println true))
* begin :
(begin
(println 'foo)
(println 'bar))
* perl->clj :
* ! not :
(! true) ;=> false
* + - * / % == != >= <= > < : only for number.
* eq ne : only for string.
* equal : for all objects.
* . : (.[perl namespace] method [^meta] args ...)
A meta can be specifed to control what type of value should be passed into perl function.
type : "scalar" "array" "hash" "ref" "nil"
^{:return type
:arguments [type ...]}
(.Language::LispPerl print "foo")
(.Language::LispPerl print ^{:return "nil" :arguments ["scalar"]} "foo") ; return nil and pass first argument as a scalar
* -> : (->[perl namespace] method args ...)
Like '.', but this will pass perl namespace as first argument to perl method.
* println
(println {:a 'a})
* trace-vars : Trace the variables in current frame.
(trace-vars)
* quote : Returns the given list as is without evaluating it
(quote (+ 1 2 )) -> (+ 1 2)
* use-lib : append path into Perl and Language::LispPerl files' searching paths.
(use-lib "path")
* ns : Language::LispPerl namespace.
(ns "foo"
(println "bar"))
* defn :
(defn foo [arg & args]
(println arg))
* defmulti :
* defmethod :
* reduce :
* map :
* file#open : open a file with a callback.
(file#open ">file"
(fn [fh]
(file#>> fn "foo")))
* file#<< : read a line from a file handler.
(file#<< fh)
* file#>> : write a string into a file handler.
(file#>> fh "foo")
Since V0.007, you have the possibility to 'freeze' the evaler into a pure perl data structure, and defrost it later on to execute some code in the same evaler state.
Usage:
my $lisp = Language::LispPerl::Evaler->new();
# Load core functions and macros
$lisp->load("core.clp");
$lisp->eval(q|(defn square [a] ( * a a ))|);
my $perl_hash = $lisp->to_hash();
# Store this pure perl hash somewhere in your favourite format.
# Hint: compress its representation as it can be quite big.
# Then later on:
my $new_lisp = Language::LispPerl::Evaler->from_hash( $perl_hash );
my $res = $new_lisp->eval(q|(square 2 )|);
Current author: Jerome Eteve ( JETEVE )
Original author: Wei Hu, huwei04@hotmail.com
Copyright 2016-2017 Jerome Eteve. All rights Reserved.
Copyright 2013 Wei Hu. All Rights Reserved.
This package as been released with the support of http://broadbean.com
Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.