There are three main phases in the algorithm:
Sanitize/format input source
Search for invalid blocks
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
Not a URI component.
This module provides instance methods for a digest implementation object to calculate message digest values.
Mixin module that provides the following:
Access to the CGI environment variables as methods. See documentation to the CGI class for a list of these variables. The methods are exposed by removing the leading HTTP_ (if it exists) and downcasing the name. For example, auth_type will return the environment variable AUTH_TYPE, and accept will return the value for HTTP_ACCEPT.
Access to cookies, including the cookies attribute.
Access to parameters, including the params attribute, and overloading [] to perform parameter value lookup by key.
The initialize_query method, for initializing the above mechanisms, handling multipart forms, and allowing the class to be used in “offline” mode.
Mixin module providing HTML generation methods.
For example,
cgi.a("http://www.example.com") { "Example" } # => "<A HREF=\"http://www.example.com\">Example</A>"
Modules Html3, Html4, etc., contain more basic HTML-generation methods (#title, #h1, etc.).
See class CGI for a detailed example.
Net::HTTP exception class. You cannot use Net::HTTPExceptions directly; instead, you must use its subclasses.
Keyword completion module. This allows partial arguments to be specified and resolved against a list of acceptable values.
Mixin methods for Gem::Command to promote available RubyGems update
Class for representing WebDAV method MOVE:
require 'net/http' uri = URI('http://example.com') hostname = uri.hostname # => "example.com" req = Net::HTTP::Move.new(uri) # => #<Net::HTTP::Move MOVE> res = Net::HTTP.start(hostname) do |http| http.request(req) end
See Request Headers.
Related:
Net::HTTP#move: sends MOVE request, returns response object.
Raised when a bad requirement is encountered
A progress reporter that prints out messages about the current progress.
An FFI closure wrapper, for handling callbacks.
closure = Class.new(Fiddle::Closure) { def call 10 end }.new(Fiddle::TYPE_INT, []) #=> #<#<Class:0x0000000150d308>:0x0000000150d240> func = Fiddle::Function.new(closure, [], Fiddle::TYPE_INT) #=> #<Fiddle::Function:0x00000001516e58> func.call #=> 10
This exception is raised if a parser error occurs.
This exception is raised if a generator or unparser error occurs.
This class works in conjunction with Psych::Parser to build an in-memory parse tree that represents a YAML document.
parser = Psych::Parser.new Psych::TreeBuilder.new parser.parse('--- foo') tree = parser.handler.root
See Psych::Handler for documentation on the event methods used in this class.
Subclass of Zlib::Error
When zlib returns a Z_MEM_ERROR, usually if there was not enough memory.
Subclass of Zlib::Error. This error is raised when the zlib stream is currently in progress.
For example:
inflater = Zlib::Inflate.new inflater.inflate(compressed) do inflater.inflate(compressed) # Raises Zlib::InProgressError end
Zlib::GzipReader is the class for reading a gzipped file. GzipReader should be used as an IO, or -IO-like, object.
Zlib::GzipReader.open('hoge.gz') {|gz| print gz.read } File.open('hoge.gz') do |f| gz = Zlib::GzipReader.new(f) print gz.read gz.close end
Method Catalogue The following methods in Zlib::GzipReader are just like their counterparts in IO, but they raise Zlib::Error or Zlib::GzipFile::Error exception if an error was found in the gzip file.
Be careful of the footer of the gzip file. A gzip file has the checksum of pre-compressed data in its footer. GzipReader checks all uncompressed data against that checksum at the following cases, and if it fails, raises Zlib::GzipFile::NoFooter, Zlib::GzipFile::CRCError, or Zlib::GzipFile::LengthError exception.
When an reading request is received beyond the end of file (the end of compressed data). That is, when Zlib::GzipReader#read, Zlib::GzipReader#gets, or some other methods for reading returns nil.
When Zlib::GzipFile#close method is called after the object reaches the end of file.
When Zlib::GzipReader#unused method is called after the object reaches the end of file.
The rest of the methods are adequately described in their own documentation.
exception to wait for reading by EAGAIN. see IO.select.
exception to wait for reading by EWOULDBLOCK. see IO.select.
exception to wait for writing by EINPROGRESS. see IO.select.