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

Represents a single line of code of a given source file

This object contains metadata about the line such as amount of indentation, if it is empty or not, and lexical data, such as if it has an ‘end` or a keyword in it.

Visibility of lines can be toggled off. Marking a line as invisible indicates that it should not be used for syntax checks. It’s functionally the same as commenting it out.

Example:

line = CodeLine.from_source("def foo\n").first
line.number => 1
line.empty? # => false
line.visible? # => true
line.mark_invisible
line.visible? # => false

Searches code for a syntax error

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

This class handles the part.

The bulk of the heavy lifting is done in:

- CodeFrontier (Holds information for generating blocks and determining if we can stop searching)
- ParseBlocksFromLine (Creates blocks into the frontier)
- BlockExpand (Expands existing blocks to search more code)

## Syntax error detection

When the frontier holds the syntax error, we can stop searching

search = CodeSearch.new(<<~EOM)
  def dog
    def lol
  end
EOM

search.call

search.invalid_blocks.map(&:to_s) # =>
# => ["def lol\n"]

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

Ripper.lex is not guaranteed to lex the entire source document

lex = LexAll.new(source: source) lex.each do |value|

puts value.line

end

Value object for accessing lex values

This lex:

[1, 0], :on_ident, "describe", CMDARG

Would translate into:

lex.line # => 1
lex.type # => :on_indent
lex.token # => "describe"

Not a URI.

URI is valid, bad usage is not.

The “file” URI is defined by RFC8089.

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)

exception to wait for reading. see IO.select.

exception to wait for writing. see IO.select.

Overview

When using Psych.load to deserialize a YAML document, the document is translated to an intermediary AST. That intermediary AST is then translated in to a Ruby object graph.

In the opposite direction, when using Psych.dump, the Ruby object graph is translated to an intermediary AST which is then converted to a YAML document.

Psych::Nodes contains all of the classes that make up the nodes of a YAML AST. You can manually build an AST and use one of the visitors (see Psych::Visitors) to convert that AST to either a YAML document or to a Ruby object graph.

Here is an example of building an AST that represents a list with one scalar:

# Create our nodes
stream = Psych::Nodes::Stream.new
doc    = Psych::Nodes::Document.new
seq    = Psych::Nodes::Sequence.new
scalar = Psych::Nodes::Scalar.new('foo')

# Build up our tree
stream.children << doc
doc.children    << seq
seq.children    << scalar

The stream is the root of the tree. We can then convert the tree to YAML:

stream.to_yaml => "---\n- foo\n"

Or convert it to Ruby:

stream.to_ruby => [["foo"]]

YAML AST Requirements

A valid YAML AST must have one Psych::Nodes::Stream at the root. A Psych::Nodes::Stream node must have 1 or more Psych::Nodes::Document nodes as children.

Psych::Nodes::Document nodes must have one and only one child. That child may be one of:

• Psych::Nodes::Sequence

• Psych::Nodes::Mapping

• Psych::Nodes::Scalar

Psych::Nodes::Sequence and Psych::Nodes::Mapping nodes may have many children, but Psych::Nodes::Mapping nodes should have an even number of children.

All of these are valid children for Psych::Nodes::Sequence and Psych::Nodes::Mapping nodes:

• Psych::Nodes::Sequence

• Psych::Nodes::Mapping

• Psych::Nodes::Scalar

• Psych::Nodes::Alias

Psych::Nodes::Scalar and Psych::Nodes::Alias are both terminal nodes and should not have any children.

The GC profiler provides access to information on GC runs including time, length and object space size.

Example:

GC::Profiler.enable

require 'rdoc/rdoc'

GC::Profiler.report

GC::Profiler.disable

See also GC.count, GC.malloc_allocated_size and GC.malloc_allocations

The Observable module extended to DRb. See Observable for details.

Extends command line arguments array (ARGV) to parse itself.

Acceptable argument classes. Now contains DecimalInteger, OctalInteger and DecimalNumeric. See Acceptable argument classes (in source code).

Raised by Encoding and String methods when the source encoding is incompatible with the target encoding.