This class is useful for exploring contents before and after a block
It searches above and below the passed in block to match for whatever criteria you give it:
Example:
def dog # 1 puts "bark" # 2 puts "bark" # 3 end # 4 scan = AroundBlockScan.new( code_lines: code_lines block: CodeBlock.new(lines: code_lines[1]) ) scan.scan_while { true } puts scan.before_index # => 0 puts scan.after_index # => 3
Contents can also be filtered using AroundBlockScan#skip
To grab the next surrounding indentation use AroundBlockScan#scan_adjacent_indent
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:
Sanitize/format input source
Search for invalid blocks
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"]
Used for formatting invalid blocks
Capture parse errors from ripper
Example:
puts RipperErrors.new(" def foo").call.errors # => ["syntax error, unexpected end-of-input, expecting ';' or '\\n'"]
Tracks which lines various code blocks have expanded to and which are still unexplored
Raised by Timeout.timeout
when the block times out.
Base class for all URI
exceptions.
Not a URI
.
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 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)
Raised when an attempt is made to send a message to a closed port, or to retrieve a message from a closed and empty port. Ports may be closed explicitly with Ractor#close_outgoing
/close_incoming and are closed implicitly when a Ractor
terminates.
r = Ractor.new { sleep(500) } r.close_outgoing r.take # Ractor::ClosedError
ClosedError
is a descendant of StopIteration
, so the closing of the ractor will break the loops without propagating the error:
r = Ractor.new do loop do msg = receive # raises ClosedError and loop traps it puts "Received: #{msg}" end puts "loop exited" end 3.times{|i| r << i} r.close_incoming r.take puts "Continue successfully"
This will print:
Received: 0 Received: 1 Received: 2 loop exited Continue successfully
ConditionVariable
objects augment class Mutex
. Using condition variables, it is possible to suspend while in the middle of a critical section until a resource becomes available.
Example:
mutex = Thread::Mutex.new resource = Thread::ConditionVariable.new a = Thread.new { mutex.synchronize { # Thread 'a' now needs the resource resource.wait(mutex) # 'a' can now have the resource } } b = Thread.new { mutex.synchronize { # Thread 'b' has finished using the resource resource.signal } }
Raised by Encoding
and String
methods when the string being transcoded contains a byte invalid for the either the source or target encoding.
Raised by transcoding methods when a named encoding does not correspond with a known converter.
An internal representation of the backtrace. The user will never interact with objects of this class directly, but class methods can be used to get backtrace settings of the current session.
AbstractSyntaxTree
provides methods to parse Ruby code into abstract syntax trees. The nodes in the tree are instances of RubyVM::AbstractSyntaxTree::Node
.
This module is MRI specific as it exposes implementation details of the MRI abstract syntax tree.
This module is experimental and its API is not stable, therefore it might change without notice. As examples, the order of children nodes is not guaranteed, the number of children nodes might change, there is no way to access children nodes by name, etc.
If you are looking for a stable API or an API working under multiple Ruby implementations, consider using the parser gem or Ripper
. If you would like to make RubyVM::AbstractSyntaxTree
stable, please join the discussion at bugs.ruby-lang.org/issues/14844.