I just asked the support guys on GitHub why AspectJ (*.aj) files are not syntax-highlighted. The answer was that they are using Pygments, but are unaware of any existing lexer for AspectJ. I did a quick web search and did not find any either. Has anyone here written one or can point me to a link for an existing one?
Long ago I have written a lexer for Kconfig (Linux kernel configuration) files, but it was rather hard for me because I do not speak Python. So before I start torturing my brain again, I thought I should better ask first instead of possibly re-inventing the wheel.
After having created a "copy, paste & modify" solution of JavaLexer initially because I really do not speak Python, I managed to hack another quick'n'dirty solution which subclasses JavaLexer and delegates lexing to it for the most part. Exceptions are
AspectJ-specific keywords,
handling of inter-type declarations followed by colons without a space not as Java labels, but as AspectJ keywords plus ":" operator and
handling of inter-type annotation declarations as AspectJ keywords and not as Java name decorators.
I am sure my little heuristic solution misses some details, but as Andrew Eisenberg said: an imperfect, but working solution is better than a non-existent perfect one:
class AspectJLexer(JavaLexer):
"""
For `AspectJ <http://www.eclipse.org/aspectj/>`_ source code.
"""
name = 'AspectJ'
aliases = ['aspectj']
filenames = ['*.aj']
mimetypes = ['text/x-aspectj']
aj_keywords = [
'aspect', 'pointcut', 'privileged', 'call', 'execution',
'initialization', 'preinitialization', 'handler', 'get', 'set',
'staticinitialization', 'target', 'args', 'within', 'withincode',
'cflow', 'cflowbelow', 'annotation', 'before', 'after', 'around',
'proceed', 'throwing', 'returning', 'adviceexecution', 'declare',
'parents', 'warning', 'error', 'soft', 'precedence', 'thisJoinPoint',
'thisJoinPointStaticPart', 'thisEnclosingJoinPointStaticPart',
'issingleton', 'perthis', 'pertarget', 'percflow', 'percflowbelow',
'pertypewithin', 'lock', 'unlock', 'thisAspectInstance'
]
aj_inter_type = ['parents:', 'warning:', 'error:', 'soft:', 'precedence:']
aj_inter_type_annotation = ['#type', '#method', '#constructor', '#field']
def get_tokens_unprocessed(self, text):
for index, token, value in JavaLexer.get_tokens_unprocessed(self, text):
if token is Name and value in self.aj_keywords:
yield index, Keyword, value
elif token is Name.Label and value in self.aj_inter_type:
yield index, Keyword, value[:-1]
yield index, Operator, value[-1]
elif token is Name.Decorator and value in self.aj_inter_type_annotation:
yield index, Keyword, value
else:
yield index, token, value
Syntax highlighting for aspectj should be quite straight forward to implement if you start with a Java lexer. The lexer would be identical to Java's with some extra keywords.
See here for a list of the AspectJ-specific keywords:
http://git.eclipse.org/c/ajdt/org.eclipse.ajdt.git/tree/org.eclipse.ajdt.core/src/org/eclipse/ajdt/core/AspectJPlugin.java
And here for the Java keywords:
http://git.eclipse.org/c/ajdt/org.eclipse.ajdt.git/tree/org.eclipse.ajdt.ui/src/org/eclipse/ajdt/internal/ui/editor/AspectJCodeScanner.java
Related
I'm trying to complete this Codewars Challenge and I'm confused as to where I'm going wrong. Could someone please give me a hand?
The question provides a "database" of translations for Welcome, and the instructions say:
Think of a way to store the languages as a database (eg an object). The languages are listed below so you can copy and paste!
Write a 'welcome' function that takes a parameter 'language' (always a string), and returns a greeting - if you have it in your database. It should default to English if the language is not in the database, or in the event of an invalid input.
My attempt:
def greet(language)
greeting = { 'english'=>'Welcome',
'czech'=>'Vitejte',
'danish'=>'Velkomst',
'dutch'=>'Welkom',
'estonian'=>'Tere tulemast',
'finnish'=>'Tervetuloa',
'flemish'=>'Welgekomen',
'french'=>'Bienvenue',
'german'=>'Willkommen',
'irish'=>'Failte',
'italian'=>'Benvenuto',
'latvian'=>'Gaidits',
'lithuanian'=>'Laukiamas',
'polish'=>'Witamy',
'spanish'=>'Bienvenido',
'swedish'=>'Valkommen',
'welsh'=>'Croeso'
}
greeting.key?(language) ? greeting.each { |k, v| return v if language == k } : 'IP_ADDRESS_INVALID'
end
To my eyes when I run my code through the IDE it seems to be working as per request but I guess I must be wrong somehow.
It's telling me it :
Expected: "Laukiamas", instead got: "Welcome"
But when I type:
p greet("lithuanian")
I get Laukiamas.
You can provide you greeting hash with a default value. It is as simple as
greeting.default = "Welcome"
This enhanced hash does all the work for you. Just look up the key; when it is not there you'll get "Welcome".
Preface
First of all, please don't post links to exercises or homework questions. Quote them in your original question to avoid link rot or additional create work for people trying to help you out.
Understanding the Problem Defined by the Linked Question
Secondly, you're misunderstanding the core question. The requirement is basically to return the Hash value for a given language key if the key exists in the Hash. If it doesn't, then return the value of the 'english' key instead. Implicit in the exercise is to understand the various types of improper inputs that would fail to find a matching key; the solution below addresses most of them, and will work even if your Ruby has frozen strings enabled.
A Working Solution
There are lots of ways to do this, but here's a simple example that will handle invalid keys, nil as a language argument, and abstract away capitalization as a potential issue.
DEFAULT_LANG = 'english'
TRANSLATIONS = {
'english' => 'Welcome',
'czech' => 'Vitejte',
'danish' => 'Velkomst',
'dutch' => 'Welkom',
'estonian' => 'Tere tulemast',
'finnish' => 'Tervetuloa',
'flemish' => 'Welgekomen',
'french' => 'Bienvenue',
'german' => 'Willkommen',
'irish' => 'Failte',
'italian' => 'Benvenuto',
'latvian' => 'Gaidits',
'lithuanian' => 'Laukiamas',
'polish' => 'Witamy',
'spanish' => 'Bienvenido',
'swedish' => 'Valkommen',
'welsh' => 'Croeso'
}
# Return a translation of "Welcome" into the language
# passed as an argument.
#
# #param language [String, #to_s] any object that can
# be coerced into a String, and therefore to
# String#downcase
# #return [String] a translation of "Welcome" or the
# string-literal +Welcome+ if no translation found
def greet language
language = language.to_s.downcase
TRANSLATIONS.fetch language, TRANSLATIONS[DEFAULT_LANG]
end
# Everything in the following Array of examples except
# +Spanish+ should return the Hash value for +english+.
['Spanish', 'Español', 123, nil].map { greet(_1) }
This will correctly return:
#=> ["Bienvenido", "Welcome", "Welcome", "Welcome"]
because only Spanish (when lower-cased) will match any of the keys currently defined in the TRANSLATIONS Hash. All the rest will use the default value defined for the exercise.
Test Results
Since there are some RSpec tests included with the linked question:
describe "Welcome! Translation" do
it "should translate input" do
Test.assert_equals(greet('english'), 'Welcome', "It didn't work out this time, keep trying!");
Test.assert_equals(greet('dutch'), 'Welkom', "It didn't work out this time, keep trying!");
Test.assert_equals(greet('IP_ADDRESS_INVALID'), 'Welcome', "It didn't work out this time, keep trying!")
end
end
The code provided not only passes the provided tests, but it also passes a number of other edge cases not defined in the unit tests. When run against the defined tests, the code above passes cleanly:
If this is homework, then you might want to create additional tests to cover all the various edge cases. You might also choose to refactor to less idiomatic code if you want more explanatory variables, more explicit intermediate conversions, or more explicit key handling. The point of good code is to be readable, so be as explicit in your code and as thorough in your tests as you need to be in order to make debugging easier.
I am trying to support Clojure's ignore text form, #_, (a sort of comment) in VS Code, which uses tmLanguage for its grammar definitions. Since it is common to disable a block of code using #_, I want the disabled block of code to retain its syntax highlighting and just italicize it, indicating its status.
But my lack of skills using tmLanguage seems to stop me. This is one of the failing attempts (a snippet of the cson):
'comment-constants':
'begin': '#_\\s*(?=\'?#?[^\\s\',"\\(\\)\\[\\]\\{\\}]+)'
'beginCaptures':
'0':
'name': 'punctuation.definition.comment.begin.clojure'
'end': '(?=[\\s\',"\\(\\)\\[\\]\\{\\}])'
'name': 'meta.comment-expression.clojure'
'patterns':
[
{
'include': '#constants'
}
]
With constants defining some Clojure constants objects, like keyword:
'keyword':
'match': '(?<=(\\s|\\(|\\[|\\{)):[\\w\\#\\.\\-\\_\\:\\+\\=\\>\\<\\/\\!\\?\\*]+(?=(\\s|\\)|\\]|\\}|\\,))'
'name': 'constant.keyword.clojure'
What I want to happen is that the constants definitions will be used ”inside” the comment. For keywords I have this (failing) spec:
it "tokenizes keywords", ->
tests =
"meta.expression.clojure": ["(:foo)"]
"meta.map.clojure": ["{:foo}"]
"meta.vector.clojure": ["[:foo]"]
"meta.quoted-expression.clojure": ["'(:foo)", "`(:foo)"]
"meta.comment-expression.clojure": ["#_:foo"]
for metaScope, lines of tests
for line in lines
{tokens} = grammar.tokenizeLine line
expect(tokens[1]).toEqual value: ":foo", scopes: ["source.clojure", metaScope, "constant.keyword.clojure"]
(The last test in that list). It fails with this message:
Expected
{ value : ':foo',
scopes : [ 'source.clojure', 'meta.comment-expression.clojure' ] }
to equal
{ value : ':foo',
scopes : [ 'source.clojure', 'meta.comment-expression.clojure', 'constant.keyword.clojure' ] }.
Meaning I am not getting the constant.keyword.clojure scope in place and thus no keyword-colorization for me. 😢
Anyone knows how to do this?
Your keyword regex starts with a lookbehind that requires that there must be a single whitespace, (, [ or { character before keywords. The _ from #_ doesn't meet that requirement.
(?<=(\\s|\\(|\\[|\\{))
You could simply add _ to the list of allowed characters:
(?<=(\\s|\\(|\\[|\\{|_))
Note that this still wouldn't work as-is for your "#_:foo" test case because of the similar lookahead at the end. You could possibly allow $ there, make the match optional, or change the test case.
I'm trying to create a validation for a predetermined list of valid brands as part of an ETL pipeline. My validation requires case insensitivity, as some brands are compound words or abbreviations that are insignificant.
I created a custom predicate, but I cannot figure out how to generate the appropriate error message.
I read the error messages doc, but am having a hard time interpreting:
How to build the syntax for my custom predicate?
Can I apply the messages in my schema class directly, without referencing an external .yml file? I looked here and it seems like it's not as straightforward as I'd hoped.
Below I've given code that represents what I have tried using both built-in predicates, and a custom one, each with their own issues. If there is a better way to compose a rule that achieves the same goal, I'd love to learn it.
require 'dry/validation'
CaseSensitiveSchema = Dry::Validation.Schema do
BRANDS = %w(several hundred valid brands)
# :included_in? from https://dry-rb.org/gems/dry-validation/basics/built-in-predicates/
required(:brand).value(included_in?: BRANDS)
end
CaseInsensitiveSchema = Dry::Validation.Schema do
BRANDS = %w(several hundred valid brands)
configure do
def in_brand_list?(value)
BRANDS.include? value.downcase
end
end
required(:brand).value(:in_brand_list?)
end
# A valid string if case insensitive
valid_product = {brand: 'Valid'}
CaseSensitiveSchema.call(valid_product).errors
# => {:brand=>["must be one of: here, are, some, valid, brands"]} # This message will be ridiculous when the full brand list is applied
CaseInsensitiveSchema.call(valid_product).errors
# => {} # Good!
invalid_product = {brand: 'Junk'}
CaseSensitiveSchema.call(invalid_product).errors
# => {:brand=>["must be one of: several, hundred, valid, brands"]} # Good... (Except this error message will contain the entire brand list!!!)
CaseInsensitiveSchema.call(invalid_product).errors
# => Dry::Validation::MissingMessageError: message for in_brand_list? was not found
# => from .. /gems/2.5.0/gems/dry-validation-0.12.2/lib/dry/validation/message_compiler.rb:116:in `visit_predicate'
The correct way to reference my error message was to reference the predicate method. No need to worry about arg, value, etc.
en:
errors:
in_brand_list?: "must be in the master brands list"
Additionally, I was able to load this error message without a separate .yml by doing this:
CaseInsensitiveSchema = Dry::Validation.Schema do
BRANDS = %w(several hundred valid brands)
configure do
def in_brand_list?(value)
BRANDS.include? value.downcase
end
def self.messages
super.merge({en: {errors: {in_brand_list?: "must be in the master brand list"}}})
end
end
required(:brand).value(:in_brand_list?)
end
I'd still love to see other implementations, specifically for a generic case-insensitive predicate. Many people say dry-rb is fantastically organized, but I find it hard to follow.
I am new to Ruby, so let me describe the context of my problem first:
I have a json as input which has the following key / value pair:
{
"service": "update"
}
The value has many different values for example: insert,delete etc.
Next there is a method x which handles the different requests:
def x(input)
case input[:service]
services = GenericService.new
when "update"
result = services.service(UpdateService.new,input)
when "insert"
result = services.service(InsertService.new,input)
when "delete"
result = services.service(DeleteService.new,input)
....
....
else
raise "Unknown service"
end
puts JSON.pretty_generate(result)
end
What is bothering me is that I still need to use a switch statement to check the String values (reminds me of 'instance of' ugh..). Is there a cleaner way (not need to use a switch)?
Finally I tried to search for an answer to my question and did not succeed, if however I missed it feel free to comment the related question.
Update: I was thinking to maybe cast the string to the related class name as follows: How do I create a class instance from a string name in ruby? and then call result = services.services(x.constantize.new,input) , then the class names ofcourse needs to match the input of the json.
You can try something like:
def x(input)
service_class_name = "#{input[:service].capitalize}Service"
service_class = Kernel.const_get(service_class_name)
service_class.new(input).process
end
In addition you might want to check if this is a valid Service class name at all.
I don't understand why you want to pass the service to GenericService this seems strange. let the service do it's job.
If you're trying to instatiate a class by it's name you're actually speaking about Reflection rather than Polymorphism.
In Ruby you can achieve this in this way:
byName = Object.const_get('YourClassName')
or if you are in a Rails app
byName= 'YourClassName'.constantize
Hope this helps
Just first thoughts, but you can do:
eval(services.service("#{input[:service].capitalize}Service.new, #{input})") if valid_service? input[:service]
def valid_service?
w%(delete update insert).include? input[:service]
end
As folks will no doubt shout, eval needs to be used with alot of care
So here is my problem.
I want to retrieve a string stored in a model and at runtime change a part of it using a variable from the rails application. Here is an example:
I have a Message model, which I use to store several unique messages. So different users have the same message, but I want to be able to show their name in the middle of the message, e.g.,
"Hi #{user.name}, ...."
I tried to store exactly that in the database but it gets escaped before showing in the view or gets interpolated when storing in the database, via the rails console.
Thanks in advance.
I don't see a reason to define custom string helper functions. Ruby offers very nice formatting approaches, e.g.:
"Hello %s" % ['world']
or
"Hello %{subject}" % { subject: 'world' }
Both examples return "Hello world".
If you want
"Hi #{user.name}, ...."
in your database, use single quotes or escape the # with a backslash to keep Ruby from interpolating the #{} stuff right away:
s = 'Hi #{user.name}, ....'
s = "Hi \#{user.name}, ...."
Then, later when you want to do the interpolation you could, if you were daring or trusted yourself, use eval:
s = pull_the_string_from_the_database
msg = eval '"' + s + '"'
Note that you'll have to turn s into a double quoted string in order for the eval to work. This will work but it isn't the nicest approach and leaves you open to all sorts of strange and confusing errors; it should be okay as long as you (or other trusted people) are writing the strings.
I think you'd be better off with a simple micro-templating system, even something as simple as this:
def fill_in(template, data)
template.gsub(/\{\{(\w+)\}\}/) { data[$1.to_sym] }
end
#...
fill_in('Hi {{user_name}}, ....', :user_name => 'Pancakes')
You could use whatever delimiters you wanted of course, I went with {{...}} because I've been using Mustache.js and Handlebars.js lately. This naive implementation has issues (no in-template formatting options, no delimiter escaping, ...) but it might be enough. If your templates get more complicated then maybe String#% or ERB might work better.
one way I can think of doing this is to have templates stored for example:
"hi name"
then have a function in models that just replaces the template tags (name) with the passed arguments.
It can also be User who logged in.
Because this new function will be a part of model, you can use it like just another field of model from anywhere in rails, including the html.erb file.
Hope that helps, let me know if you need more description.
Adding another possible solution using Procs:
#String can be stored in the database
string = "->(user){ 'Hello ' + user.name}"
proc = eval(string)
proc.call(User.find(1)) #=> "Hello Bob"
gsub is very powerful in Ruby.
It takes a hash as a second argument so you can supply it with a whitelist of keys to replace like that:
template = <<~STR
Hello %{user_email}!
You have %{user_voices_count} votes!
Greetings from the system
STR
template.gsub(/%{.*?}/, {
"%{user_email}" => 'schmijos#example.com',
"%{user_voices_count}" => 5,
"%{release_distributable_total}" => 131,
"%{entitlement_value}" => 2,
})
Compared to ERB it's secure. And it doesn't complain about single % and unused or inexistent keys like string interpolation with %(sprintf) does.