Parses the given string into an abstract syntax tree, returning the root node of that tree.
RubyVM::AbstractSyntaxTree.parse("x = 1 + 2") # => #<RubyVM::AbstractSyntaxTree::Node:SCOPE@1:0-1:9>
If keep_script_lines: true option is provided, the text of the parsed source is associated with nodes and is available via Node#script_lines.
If keep_tokens: true option is provided, Node#tokens are populated.
SyntaxError is raised if the given string is invalid syntax. To overwrite this behavior, error_tolerant: true can be provided. In this case, the parser will produce a tree where expressions with syntax errors would be represented by Node with type=:ERROR.
root = RubyVM::AbstractSyntaxTree.parse("x = 1; p(x; y=2") # <internal:ast>:33:in `parse': syntax error, unexpected ';', expecting ')' (SyntaxError) # x = 1; p(x; y=2 # ^ root = RubyVM::AbstractSyntaxTree.parse("x = 1; p(x; y=2", error_tolerant: true) # (SCOPE@1:0-1:15 # tbl: [:x, :y] # args: nil # body: (BLOCK@1:0-1:15 (LASGN@1:0-1:5 :x (LIT@1:4-1:5 1)) (ERROR@1:7-1:11) (LASGN@1:12-1:15 :y (LIT@1:14-1:15 2)))) root.children.last.children # [(LASGN@1:0-1:5 :x (LIT@1:4-1:5 1)), # (ERROR@1:7-1:11), # (LASGN@1:12-1:15 :y (LIT@1:14-1:15 2))]
Note that parsing continues even after the errored expresion.
Like getc, but raises an exception if already at end-of-stream; see Character IO.
Similar to read, but raises EOFError at end of string instead of returning nil, as well as IO#sysread does.
Reads at most maxlen bytes from the stream. If buf is provided it must reference a string which will receive the data.
See IO#readpartial for full details.
Reads a one-character string from the stream. Raises an EOFError at end of file.
If a block is given, it prints out each of the elements encountered. Block parameters are (in that order):
depth: The recursion depth, plus one with each constructed value being encountered (Integer)
offset: Current byte offset (Integer)
header length: Combined length in bytes of the Tag and Length headers. (Integer)
length: The overall remaining length of the entire data (Integer)
constructed: Whether this value is constructed or not (Boolean)
tag_class: Current tag class (Symbol)
tag: The current tag number (Integer)
der = File.binread('asn1data.der') OpenSSL::ASN1.traverse(der) do | depth, offset, header_len, length, constructed, tag_class, tag| puts "Depth: #{depth} Offset: #{offset} Length: #{length}" puts "Header length: #{header_len} Tag: #{tag} Tag class: #{tag_class} Constructed: #{constructed}" end
Start streaming using encoding
Clears the GC profiler data.
Returns whether the form contained multipart/form-data
Generate a TextArea element, as a String.
name is the name of the textarea. cols is the number of columns and rows is the number of rows in the display.
Alternatively, the attributes can be specified as a hash.
The body is provided by the passed-in no-argument block
textarea("name") # = textarea("NAME" => "name", "COLS" => 70, "ROWS" => 10) textarea("name", 40, 5) # = textarea("NAME" => "name", "COLS" => 40, "ROWS" => 5)
Returns an array of Range objects that represent the value of field 'Range', or nil if there is no such field; see Range request header:
req = Net::HTTP::Get.new(uri) req['Range'] = 'bytes=0-99,200-299,400-499' req.range # => [0..99, 200..299, 400..499] req.delete('Range') req.range # # => nil
returns a charset parameter in Content-Type field. It is downcased for canonicalization.
If charset parameter is not given but a block is given, the block is called and its result is returned. It can be used to guess charset.
If charset parameter and block is not given, nil is returned except text type. In that case, “utf-8” is returned as defined by RFC6838 4.2.1
Parses self destructively and returns self containing the rest arguments left unparsed.
Generates formatted random number from raw random bytes. See Random#rand.
Displays the given statement on the standard output (or equivalent).
Load extra data embed into binary format String object.
Returns an array of the grapheme clusters in self (see Unicode Grapheme Cluster Boundaries):
s = "\u0061\u0308-pqr-\u0062\u0308-xyz-\u0063\u0308" # => "ä-pqr-b̈-xyz-c̈" s.grapheme_clusters # => ["ä", "-", "p", "q", "r", "-", "b̈", "-", "x", "y", "z", "-", "c̈"]
Returns whether self starts with any of the given string_or_regexp.
Matches patterns against the beginning of self. For each given string_or_regexp, the pattern is:
string_or_regexp itself, if it is a Regexp.
Regexp.quote(string_or_regexp), if string_or_regexp is a string.
Returns true if any pattern matches the beginning, false otherwise:
'hello'.start_with?('hell') # => true 'hello'.start_with?(/H/i) # => true 'hello'.start_with?('heaven', 'hell') # => true 'hello'.start_with?('heaven', 'paradise') # => false 'тест'.start_with?('т') # => true 'こんにちは'.start_with?('こ') # => true
Related: String#end_with?.
Calls the given block with each successive character from self; returns self:
'hello'.each_char {|char| print char, ' ' } print "\n" 'тест'.each_char {|char| print char, ' ' } print "\n" 'こんにちは'.each_char {|char| print char, ' ' } print "\n"
Output:
h e l l o т е с т こ ん に ち は
Returns an enumerator if no block is given.
Like backtrace, but returns each line of the execution stack as a Thread::Backtrace::Location. Accepts the same arguments as backtrace.
f = Fiber.new { Fiber.yield } f.resume loc = f.backtrace_locations.first loc.label #=> "yield" loc.path #=> "test.rb" loc.lineno #=> 1