Results for: "Logger"

Multiple lines form a singular CodeBlock

Source code is made of multiple CodeBlocks.

Example:

code_block.to_s # =>
  #   def foo
  #     puts "foo"
  #   end

code_block.valid? # => true
code_block.in_valid? # => false

There are three main phases in the algorithm:

1. Sanitize/format input source

2. Search for invalid blocks

3. Format invalid blocks into something meaninful

The Code frontier is a critical part of the second step

## Knowing where we’ve been

Once a code block is generated it is added onto the frontier. Then it will be sorted by indentation and frontier can be filtered. Large blocks that fully enclose a smaller block will cause the smaller block to be evicted.

CodeFrontier#<<(block) # Adds block to frontier
CodeFrontier#pop # Removes block from frontier

## Knowing where we can go

Internally the frontier keeps track of “unvisited” lines which are exposed via ‘next_indent_line` when called, this method returns, a line of code with the highest indentation.

The returned line of code can be used to build a CodeBlock and then that code block is added back to the frontier. Then, the lines are removed from the “unvisited” so we don’t double-create the same block.

CodeFrontier#next_indent_line # Shows next line
CodeFrontier#register_indent_block(block) # Removes lines from unvisited

## Knowing when to stop

The frontier knows how to check the entire document for a syntax error. When blocks are added onto the frontier, they’re removed from the document. When all code containing syntax errors has been added to the frontier, the document will be parsable without a syntax error and the search can stop.

CodeFrontier#holds_all_syntax_errors? # Returns true when frontier holds all syntax errors

## Filtering false positives

Once the search is completed, the frontier may have multiple blocks that do not contain the syntax error. To limit the result to the smallest subset of “invalid blocks” call:

CodeFrontier#detect_invalid_blocks

Outputs code with highlighted lines

Whatever is passed to this class will be rendered even if it is “marked invisible” any filtering of output should be done before calling this class.

DisplayCodeWithLineNumbers.new(
  lines: lines,
  highlight_lines: [lines[2], lines[3]]
).call
# =>
    1
    2  def cat
  > 3    Dir.chdir
  > 4    end
    5  end
    6

Used for formatting invalid blocks

This class is responsible for generating initial code blocks that will then later be expanded.

The biggest concern when guessing code blocks, is accidentally grabbing one that contains only an “end”. In this example:

def dog
  begonn # mispelled `begin`
  puts "bark"
  end
end

The following lines would be matched (from bottom to top):

1) end

2) puts "bark"
   end

3) begonn
   puts "bark"
   end

At this point it has no where else to expand, and it will yield this inner code as a block

Converts a SyntaxError message to a path

Handles the case where the filename has a colon in it such as on a windows file system: github.com/ruby/syntax_suggest/issues/111

Example:

message = "/tmp/scratch:2:in `require_relative': /private/tmp/bad.rb:1: syntax error, unexpected `end' (SyntaxError)"
puts PathnameFromMessage.new(message).call.name
# => "/tmp/scratch.rb"

Raised by Timeout.timeout when the block times out.

Base class for all URI exceptions.

Not a URI.

Not a URI component.

URI is valid, bad usage is not.

Class that parses String’s into URI’s.

It contains a Hash set of patterns and Regexp’s that match and validate.

RefError is raised when a referenced object has been recycled by the garbage collector

Raised when a mathematical function is evaluated outside of its domain of definition.

For example, since cos returns values in the range -1..1, its inverse function acos is only defined on that interval:

Math.acos(42)

produces:

Math::DomainError: Numerical argument is out of domain - "acos"

Raised on attempt to Ractor#take if there was an uncaught exception in the Ractor. Its cause will contain the original exception, and ractor is the original ractor it was raised in.

r = Ractor.new { raise "Something weird happened" }

begin
  r.take
rescue => e
  p e             # => #<Ractor::RemoteError: thrown by remote Ractor.>
  p e.ractor == r # => true
  p e.cause       # => #<RuntimeError: Something weird happened>
end

Raised on an attempt to access an object which was moved in Ractor#send or Ractor.yield.

r = Ractor.new { sleep }

ary = [1, 2, 3]
r.send(ary, move: true)
ary.inspect
# Ractor::MovedError (can not send any methods to a moved object)

This is not an existing class, but documentation of the interface that Scheduler object should comply to in order to be used as argument to Fiber.scheduler and handle non-blocking fibers. See also the “Non-blocking fibers” section in Fiber class docs for explanations of some concepts.

Scheduler’s behavior and usage are expected to be as follows:

• When the execution in the non-blocking Fiber reaches some blocking operation (like sleep, wait for a process, or a non-ready I/O), it calls some of the scheduler’s hook methods, listed below.

• Scheduler somehow registers what the current fiber is waiting on, and yields control to other fibers with Fiber.yield (so the fiber would be suspended while expecting its wait to end, and other fibers in the same thread can perform)

• At the end of the current thread execution, the scheduler’s method scheduler_close is called

• The scheduler runs into a wait loop, checking all the blocked fibers (which it has registered on hook calls) and resuming them when the awaited resource is ready (e.g. I/O ready or sleep time elapsed).

This way concurrent execution will be achieved transparently for every individual Fiber’s code.

Scheduler implementations are provided by gems, like Async.

Hook methods are:

• io_wait, io_read, io_write, io_pread, io_pwrite, and io_select, io_close

• process_wait

• kernel_sleep

• timeout_after

• address_resolve

• block and unblock

• (the list is expanded as Ruby developers make more methods having non-blocking calls)

When not specified otherwise, the hook implementations are mandatory: if they are not implemented, the methods trying to call hook will fail. To provide backward compatibility, in the future hooks will be optional (if they are not implemented, due to the scheduler being created for the older Ruby version, the code which needs this hook will not fail, and will just behave in a blocking fashion).

It is also strongly recommended that the scheduler implements the fiber method, which is delegated to by Fiber.schedule.

Sample toy implementation of the scheduler can be found in Ruby’s code, in test/fiber/scheduler.rb

Raised by Encoding and String methods when the string being transcoded contains a byte invalid for the either the source or target encoding.

A mixin that provides methods for parsing C struct and prototype signatures.

Example

require 'fiddle/import'

include Fiddle::CParser
  #=> Object

parse_ctype('int')
  #=> Fiddle::TYPE_INT

parse_struct_signature(['int i', 'char c'])
  #=> [[Fiddle::TYPE_INT, Fiddle::TYPE_CHAR], ["i", "c"]]

parse_signature('double sum(double, double)')
  #=> ["sum", Fiddle::TYPE_DOUBLE, [Fiddle::TYPE_DOUBLE, Fiddle::TYPE_DOUBLE]]

A DSL that provides the means to dynamically load libraries and build modules around them including calling extern functions within the C library that has been loaded.

Example

require 'fiddle'
require 'fiddle/import'

module LibSum
  extend Fiddle::Importer
  dlload './libsum.so'
  extern 'double sum(double*, int)'
  extern 'double split(double)'
end

Used to construct C classes (CUnion, CStruct, etc)

Fiddle::Importer#struct and Fiddle::Importer#union wrap this functionality in an easy-to-use manner.