зеркало из https://github.com/github/ruby.git
777 строки
24 KiB
Ruby
777 строки
24 KiB
Ruby
# frozen_string_literal: false
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# scanf for Ruby
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#
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#--
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# $Release Version: 1.1.2 $
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# $Revision$
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# $Id$
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# $Author$
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#++
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#
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# == Description
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#
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# scanf is an implementation of the C function scanf(3), modified as necessary
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# for Ruby compatibility.
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#
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# The methods provided are String#scanf, IO#scanf, and
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# Kernel#scanf. Kernel#scanf is a wrapper around STDIN.scanf. IO#scanf
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# can be used on any IO stream, including file handles and sockets.
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# scanf can be called either with or without a block.
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#
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# Scanf scans an input string or stream according to a <b>format</b>, as
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# described below in Conversions, and returns an array of matches between
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# the format and the input. The format is defined in a string, and is
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# similar (though not identical) to the formats used in Kernel#printf and
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# Kernel#sprintf.
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#
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# The format may contain <b>conversion specifiers</b>, which tell scanf
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# what form (type) each particular matched substring should be converted
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# to (e.g., decimal integer, floating point number, literal string,
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# etc.) The matches and conversions take place from left to right, and
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# the conversions themselves are returned as an array.
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#
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# The format string may also contain characters other than those in the
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# conversion specifiers. Whitespace (blanks, tabs, or newlines) in the
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# format string matches any amount of whitespace, including none, in
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# the input. Everything else matches only itself.
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#
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# Scanning stops, and scanf returns, when any input character fails to
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# match the specifications in the format string, or when input is
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# exhausted, or when everything in the format string has been
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# matched. All matches found up to the stopping point are returned in
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# the return array (or yielded to the block, if a block was given).
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#
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#
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# == Basic usage
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#
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# require 'scanf'
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#
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# # String#scanf and IO#scanf take a single argument, the format string
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# array = a_string.scanf("%d%s")
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# array = an_io.scanf("%d%s")
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#
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# # Kernel#scanf reads from STDIN
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# array = scanf("%d%s")
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#
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# == Block usage
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#
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# When called with a block, scanf keeps scanning the input, cycling back
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# to the beginning of the format string, and yields a new array of
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# conversions to the block every time the format string is matched
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# (including partial matches, but not including complete failures). The
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# actual return value of scanf when called with a block is an array
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# containing the results of all the executions of the block.
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#
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# str = "123 abc 456 def 789 ghi"
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# str.scanf("%d%s") { |num,str| [ num * 2, str.upcase ] }
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# # => [[246, "ABC"], [912, "DEF"], [1578, "GHI"]]
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#
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# == Conversions
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#
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# The single argument to scanf is a format string, which generally
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# includes one or more conversion specifiers. Conversion specifiers
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# begin with the percent character ('%') and include information about
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# what scanf should next scan for (string, decimal number, single
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# character, etc.).
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#
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# There may be an optional maximum field width, expressed as a decimal
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# integer, between the % and the conversion. If no width is given, a
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# default of `infinity' is used (with the exception of the %c specifier;
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# see below). Otherwise, given a field width of <em>n</em> for a given
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# conversion, at most <em>n</em> characters are scanned in processing
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# that conversion. Before conversion begins, most conversions skip
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# whitespace in the input string; this whitespace is not counted
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# against the field width.
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#
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# The following conversions are available.
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#
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# [%]
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# Matches a literal `%'. That is, `%%' in the format string matches a
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# single input `%' character. No conversion is done, and the resulting
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# '%' is not included in the return array.
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#
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# [d]
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# Matches an optionally signed decimal integer.
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#
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# [u]
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# Same as d.
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#
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# [i]
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# Matches an optionally signed integer. The integer is read in base
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# 16 if it begins with `0x' or `0X', in base 8 if it begins with `0',
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# and in base 10 other- wise. Only characters that correspond to the
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# base are recognized.
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#
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# [o]
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# Matches an optionally signed octal integer.
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#
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# [x, X]
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# Matches an optionally signed hexadecimal integer,
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#
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# [a, e, f, g, A, E, F, G]
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# Matches an optionally signed floating-point number.
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#
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# [s]
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# Matches a sequence of non-white-space character. The input string stops at
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# whitespace or at the maximum field width, whichever occurs first.
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#
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# [c]
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# Matches a single character, or a sequence of <em>n</em> characters if a
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# field width of <em>n</em> is specified. The usual skip of leading white
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# space is suppressed. To skip whitespace first, use an explicit space in
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# the format.
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#
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# [[]
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# Matches a nonempty sequence of characters from the specified set
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# of accepted characters. The usual skip of leading whitespace is
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# suppressed. This bracketed sub-expression is interpreted exactly like a
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# character class in a Ruby regular expression. (In fact, it is placed as-is
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# in a regular expression.) The matching against the input string ends with
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# the appearance of a character not in (or, with a circumflex, in) the set,
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# or when the field width runs out, whichever comes first.
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#
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# === Assignment suppression
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#
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# To require that a particular match occur, but without including the result
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# in the return array, place the <b>assignment suppression flag</b>, which is
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# the star character ('*'), immediately after the leading '%' of a format
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# specifier (just before the field width, if any).
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#
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# == scanf for Ruby compared with scanf in C
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#
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# scanf for Ruby is based on the C function scanf(3), but with modifications,
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# dictated mainly by the underlying differences between the languages.
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#
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# === Unimplemented flags and specifiers
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#
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# * The only flag implemented in scanf for Ruby is '<tt>*</tt>' (ignore
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# upcoming conversion). Many of the flags available in C versions of
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# scanf(3) have to do with the type of upcoming pointer arguments, and are
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# meaningless in Ruby.
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#
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# * The <tt>n</tt> specifier (store number of characters consumed so far in
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# next pointer) is not implemented.
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#
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# * The <tt>p</tt> specifier (match a pointer value) is not implemented.
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#
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# === Altered specifiers
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#
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# [o, u, x, X]
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# In scanf for Ruby, all of these specifiers scan for an optionally signed
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# integer, rather than for an unsigned integer like their C counterparts.
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#
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# === Return values
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#
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# scanf for Ruby returns an array of successful conversions, whereas
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# scanf(3) returns the number of conversions successfully
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# completed. (See below for more details on scanf for Ruby's return
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# values.)
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#
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# == Return values
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#
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# Without a block, scanf returns an array containing all the conversions
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# it has found. If none are found, scanf will return an empty array. An
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# unsuccessful match is never ignored, but rather always signals the end
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# of the scanning operation. If the first unsuccessful match takes place
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# after one or more successful matches have already taken place, the
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# returned array will contain the results of those successful matches.
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#
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# With a block scanf returns a 'map'-like array of transformations from
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# the block -- that is, an array reflecting what the block did with each
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# yielded result from the iterative scanf operation. (See "Block
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# usage", above.)
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#
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# == Current limitations and bugs
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#
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# When using IO#scanf under Windows, make sure you open your files in
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# binary mode:
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#
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# File.open("filename", "rb")
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#
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# so that scanf can keep track of characters correctly.
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#
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# Support for character classes is reasonably complete (since it
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# essentially piggy-backs on Ruby's regular expression handling of
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# character classes), but users are advised that character class testing
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# has not been exhaustive, and that they should exercise some caution
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# in using any of the more complex and/or arcane character class
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# idioms.
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#
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# == License and copyright
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#
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# Copyright:: (c) 2002-2003 David Alan Black
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# License:: Distributed on the same licensing terms as Ruby itself
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#
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# == Warranty disclaimer
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#
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# This software is provided "as is" and without any express or implied
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# warranties, including, without limitation, the implied warranties of
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# merchantability and fitness for a particular purpose.
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#
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# == Credits and acknowledgements
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#
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# scanf was developed as the major activity of the Austin Ruby Codefest
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# (Austin, Texas, August 2002).
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#
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# Principal author:: David Alan Black (mailto:dblack@superlink.net)
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# Co-author:: Hal Fulton (mailto:hal9000@hypermetrics.com)
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# Project contributors:: Nolan Darilek, Jason Johnston
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#
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# Thanks to Hal Fulton for hosting the Codefest.
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#
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# Thanks to Matz for suggestions about the class design.
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#
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# Thanks to Gavin Sinclair for some feedback on the documentation.
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#
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# The text for parts of this document, especially the Description and
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# Conversions sections, above, were adapted from the Linux Programmer's
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# Manual manpage for scanf(3), dated 1995-11-01.
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#
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# == Bugs and bug reports
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#
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# scanf for Ruby is based on something of an amalgam of C scanf
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# implementations and documentation, rather than on a single canonical
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# description. Suggestions for features and behaviors which appear in
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# other scanfs, and would be meaningful in Ruby, are welcome, as are
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# reports of suspicious behaviors and/or bugs. (Please see "Credits and
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# acknowledgements", above, for email addresses.)
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module Scanf
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# :stopdoc:
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# ==Technical notes
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#
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# ===Rationale behind scanf for Ruby
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#
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# The impetus for a scanf implementation in Ruby comes chiefly from the fact
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# that existing pattern matching operations, such as Regexp#match and
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# String#scan, return all results as strings, which have to be converted to
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# integers or floats explicitly in cases where what's ultimately wanted are
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# integer or float values.
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#
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# ===Design of scanf for Ruby
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#
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# scanf for Ruby is essentially a <format string>-to-<regular
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# expression> converter.
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#
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# When scanf is called, a FormatString object is generated from the
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# format string ("%d%s...") argument. The FormatString object breaks the
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# format string down into atoms ("%d", "%5f", "blah", etc.), and from
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# each atom it creates a FormatSpecifier object, which it
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# saves.
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#
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# Each FormatSpecifier has a regular expression fragment and a "handler"
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# associated with it. For example, the regular expression fragment
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# associated with the format "%d" is "([-+]?\d+)", and the handler
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# associated with it is a wrapper around String#to_i. scanf itself calls
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# FormatString#match, passing in the input string. FormatString#match
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# iterates through its FormatSpecifiers; for each one, it matches the
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# corresponding regular expression fragment against the string. If
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# there's a match, it sends the matched string to the handler associated
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# with the FormatSpecifier.
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#
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# Thus, to follow up the "%d" example: if "123" occurs in the input
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# string when a FormatSpecifier consisting of "%d" is reached, the "123"
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# will be matched against "([-+]?\d+)", and the matched string will be
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# rendered into an integer by a call to to_i.
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#
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# The rendered match is then saved to an accumulator array, and the
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# input string is reduced to the post-match substring. Thus the string
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# is "eaten" from the left as the FormatSpecifiers are applied in
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# sequence. (This is done to a duplicate string; the original string is
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# not altered.)
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#
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# As soon as a regular expression fragment fails to match the string, or
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# when the FormatString object runs out of FormatSpecifiers, scanning
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# stops and results accumulated so far are returned in an array.
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class FormatSpecifier
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attr_reader :re_string, :matched_string, :conversion, :matched
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private
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def skip; /^\s*%\*/.match(@spec_string); end
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def extract_float(s)
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return nil unless s &&! skip
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if /\A(?<sign>[-+]?)0[xX](?<frac>\.\h+|\h+(?:\.\h*)?)[pP](?<exp>[-+]?\d+)/ =~ s
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f1, f2 = frac.split('.')
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f = f1.hex
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if f2
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len = f2.length
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if len > 0
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f += f2.hex / (16.0 ** len)
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end
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end
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(sign == ?- ? -1 : 1) * Math.ldexp(f, exp.to_i)
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elsif /\A([-+]?\d+)\.([eE][-+]\d+)/ =~ s
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($1 << $2).to_f
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else
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s.to_f
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end
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end
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def extract_decimal(s); s.to_i if s &&! skip; end
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def extract_hex(s); s.hex if s &&! skip; end
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def extract_octal(s); s.oct if s &&! skip; end
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def extract_integer(s); Integer(s) if s &&! skip; end
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def extract_plain(s); s unless skip; end
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def nil_proc(s); nil; end
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public
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def to_s
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@spec_string
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end
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def count_space?
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/(?:\A|\S)%\*?\d*c|%\d*\[/.match(@spec_string)
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end
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def initialize(str)
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@spec_string = str
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h = '[A-Fa-f0-9]'
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@re_string, @handler =
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case @spec_string
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# %[[:...:]]
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when /%\*?(\[\[:[a-z]+:\]\])/
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[ "(#{$1}+)", :extract_plain ]
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# %5[[:...:]]
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when /%\*?(\d+)(\[\[:[a-z]+:\]\])/
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[ "(#{$2}{1,#{$1}})", :extract_plain ]
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# %[...]
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when /%\*?\[([^\]]*)\]/
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yes = $1
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if /^\^/.match(yes) then no = yes[1..-1] else no = '^' + yes end
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[ "([#{yes}]+)(?=[#{no}]|\\z)", :extract_plain ]
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# %5[...]
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when /%\*?(\d+)\[([^\]]*)\]/
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yes = $2
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w = $1
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[ "([#{yes}]{1,#{w}})", :extract_plain ]
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# %i
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when /%\*?i/
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[ "([-+]?(?:(?:0[0-7]+)|(?:0[Xx]#{h}+)|(?:[1-9]\\d*)))", :extract_integer ]
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# %5i
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when /%\*?(\d+)i/
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n = $1.to_i
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s = "("
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if n > 1 then s += "[1-9]\\d{1,#{n-1}}|" end
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if n > 1 then s += "0[0-7]{1,#{n-1}}|" end
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if n > 2 then s += "[-+]0[0-7]{1,#{n-2}}|" end
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if n > 2 then s += "[-+][1-9]\\d{1,#{n-2}}|" end
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if n > 2 then s += "0[Xx]#{h}{1,#{n-2}}|" end
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if n > 3 then s += "[-+]0[Xx]#{h}{1,#{n-3}}|" end
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s += "\\d"
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s += ")"
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[ s, :extract_integer ]
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# %d, %u
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when /%\*?[du]/
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[ '([-+]?\d+)', :extract_decimal ]
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# %5d, %5u
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when /%\*?(\d+)[du]/
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n = $1.to_i
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s = "("
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if n > 1 then s += "[-+]\\d{1,#{n-1}}|" end
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s += "\\d{1,#{$1}})"
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[ s, :extract_decimal ]
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# %x
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when /%\*?[Xx]/
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[ "([-+]?(?:0[Xx])?#{h}+)", :extract_hex ]
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# %5x
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when /%\*?(\d+)[Xx]/
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n = $1.to_i
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s = "("
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if n > 3 then s += "[-+]0[Xx]#{h}{1,#{n-3}}|" end
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if n > 2 then s += "0[Xx]#{h}{1,#{n-2}}|" end
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if n > 1 then s += "[-+]#{h}{1,#{n-1}}|" end
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s += "#{h}{1,#{n}}"
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s += ")"
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[ s, :extract_hex ]
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# %o
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when /%\*?o/
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[ '([-+]?[0-7]+)', :extract_octal ]
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# %5o
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when /%\*?(\d+)o/
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[ "([-+][0-7]{1,#{$1.to_i-1}}|[0-7]{1,#{$1}})", :extract_octal ]
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# %f
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when /%\*?[aefgAEFG]/
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[ '([-+]?(?:0[xX](?:\.\h+|\h+(?:\.\h*)?)[pP][-+]?\d+|\d+(?![\d.])|\d*\.\d*(?:[eE][-+]?\d+)?))', :extract_float ]
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# %5f
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when /%\*?(\d+)[aefgAEFG]/
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[ '(?=[-+]?(?:0[xX](?:\.\h+|\h+(?:\.\h*)?)[pP][-+]?\d+|\d+(?![\d.])|\d*\.\d*(?:[eE][-+]?\d+)?))' +
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"(\\S{1,#{$1}})", :extract_float ]
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# %5s
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when /%\*?(\d+)s/
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[ "(\\S{1,#{$1}})", :extract_plain ]
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# %s
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when /%\*?s/
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[ '(\S+)', :extract_plain ]
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# %c
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when /\s%\*?c/
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[ "\\s*(.)", :extract_plain ]
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# %c
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when /%\*?c/
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[ "(.)", :extract_plain ]
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# %5c (whitespace issues are handled by the count_*_space? methods)
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when /%\*?(\d+)c/
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[ "(.{1,#{$1}})", :extract_plain ]
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# %%
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when /%%/
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[ '(\s*%)', :nil_proc ]
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# literal characters
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else
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[ "(#{Regexp.escape(@spec_string)})", :nil_proc ]
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end
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@re_string = '\A' + @re_string
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end
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def to_re
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Regexp.new(@re_string,Regexp::MULTILINE)
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end
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def match(str)
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@matched = false
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s = str.dup
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s.sub!(/\A\s+/,'') unless count_space?
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res = to_re.match(s)
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if res
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@conversion = send(@handler, res[1])
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@matched_string = @conversion.to_s
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@matched = true
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end
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res
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end
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def letter
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@spec_string[/%\*?\d*([a-z\[])/, 1]
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end
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def width
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|
@spec_string[/%\*?(\d+)/, 1]&.to_i
|
|
end
|
|
|
|
def mid_match?
|
|
return false unless @matched
|
|
cc_no_width = letter == '[' &&! width
|
|
c_or_cc_width = (letter == 'c' || letter == '[') && width
|
|
width_left = c_or_cc_width && (matched_string.size < width)
|
|
|
|
return width_left || cc_no_width
|
|
end
|
|
|
|
end
|
|
|
|
class FormatString
|
|
|
|
attr_reader :string_left, :last_spec_tried,
|
|
:last_match_tried, :matched_count, :space
|
|
|
|
SPECIFIERS = 'diuXxofFeEgGscaA'
|
|
REGEX = /
|
|
# possible space, followed by...
|
|
(?:\s*
|
|
# percent sign, followed by...
|
|
%
|
|
# another percent sign, or...
|
|
(?:%|
|
|
# optional assignment suppression flag
|
|
\*?
|
|
# optional maximum field width
|
|
\d*
|
|
# named character class, ...
|
|
(?:\[\[:\w+:\]\]|
|
|
# traditional character class, or...
|
|
\[[^\]]*\]|
|
|
# specifier letter.
|
|
[#{SPECIFIERS}])))|
|
|
# or miscellaneous characters
|
|
[^%\s]+/ix
|
|
|
|
def initialize(str)
|
|
@specs = []
|
|
@i = 1
|
|
s = str.to_s
|
|
return unless /\S/.match(s)
|
|
@space = true if /\s\z/.match(s)
|
|
@specs.replace s.scan(REGEX).map {|spec| FormatSpecifier.new(spec) }
|
|
end
|
|
|
|
def to_s
|
|
@specs.join('')
|
|
end
|
|
|
|
def prune(n=matched_count)
|
|
n.times { @specs.shift }
|
|
end
|
|
|
|
def spec_count
|
|
@specs.size
|
|
end
|
|
|
|
def last_spec
|
|
@i == spec_count - 1
|
|
end
|
|
|
|
def match(str)
|
|
accum = []
|
|
@string_left = str
|
|
@matched_count = 0
|
|
|
|
@specs.each_with_index do |spec,i|
|
|
@i=i
|
|
@last_spec_tried = spec
|
|
@last_match_tried = spec.match(@string_left)
|
|
break unless @last_match_tried
|
|
@matched_count += 1
|
|
|
|
accum << spec.conversion
|
|
|
|
@string_left = @last_match_tried.post_match
|
|
break if @string_left.empty?
|
|
end
|
|
return accum.compact
|
|
end
|
|
end
|
|
# :startdoc:
|
|
end
|
|
|
|
class IO
|
|
|
|
#:stopdoc:
|
|
# The trick here is doing a match where you grab one *line*
|
|
# of input at a time. The linebreak may or may not occur
|
|
# at the boundary where the string matches a format specifier.
|
|
# And if it does, some rule about whitespace may or may not
|
|
# be in effect...
|
|
#
|
|
# That's why this is much more elaborate than the string
|
|
# version.
|
|
#
|
|
# For each line:
|
|
#
|
|
# Match succeeds (non-emptily)
|
|
# and the last attempted spec/string sub-match succeeded:
|
|
#
|
|
# could the last spec keep matching?
|
|
# yes: save interim results and continue (next line)
|
|
#
|
|
# The last attempted spec/string did not match:
|
|
#
|
|
# are we on the next-to-last spec in the string?
|
|
# yes:
|
|
# is fmt_string.string_left all spaces?
|
|
# yes: does current spec care about input space?
|
|
# yes: fatal failure
|
|
# no: save interim results and continue
|
|
# no: continue [this state could be analyzed further]
|
|
#
|
|
#:startdoc:
|
|
|
|
# Scans the current string until the match is exhausted,
|
|
# yielding each match as it is encountered in the string.
|
|
# A block is not necessary though, as the results will simply
|
|
# be aggregated into the final array.
|
|
#
|
|
# "123 456".block_scanf("%d")
|
|
# # => [123, 456]
|
|
#
|
|
# If a block is given, the value from that is returned from
|
|
# the yield is added to an output array.
|
|
#
|
|
# "123 456".block_scanf("%d") do |digit,| # the ',' unpacks the Array
|
|
# digit + 100
|
|
# end
|
|
# # => [223, 556]
|
|
#
|
|
# See Scanf for details on creating a format string.
|
|
#
|
|
# You will need to require 'scanf' to use IO#scanf.
|
|
def scanf(str,&b) #:yield: current_match
|
|
return block_scanf(str,&b) if b
|
|
return [] unless str.size > 0
|
|
|
|
start_position = pos rescue 0
|
|
matched_so_far = 0
|
|
source_buffer = ""
|
|
result_buffer = []
|
|
final_result = []
|
|
|
|
fstr = Scanf::FormatString.new(str)
|
|
|
|
loop do
|
|
if eof || (tty? &&! fstr.match(source_buffer))
|
|
final_result.concat(result_buffer)
|
|
break
|
|
end
|
|
|
|
source_buffer << gets
|
|
|
|
current_match = fstr.match(source_buffer)
|
|
|
|
spec = fstr.last_spec_tried
|
|
|
|
if spec.matched
|
|
if spec.mid_match?
|
|
result_buffer.replace(current_match)
|
|
next
|
|
end
|
|
|
|
elsif (fstr.matched_count == fstr.spec_count - 1)
|
|
if /\A\s*\z/.match(fstr.string_left)
|
|
break if spec.count_space?
|
|
result_buffer.replace(current_match)
|
|
next
|
|
end
|
|
end
|
|
|
|
final_result.concat(current_match)
|
|
|
|
matched_so_far += source_buffer.size
|
|
source_buffer.replace(fstr.string_left)
|
|
matched_so_far -= source_buffer.size
|
|
break if fstr.last_spec
|
|
fstr.prune
|
|
end
|
|
|
|
begin
|
|
seek(start_position + matched_so_far, IO::SEEK_SET)
|
|
rescue Errno::ESPIPE
|
|
end
|
|
|
|
soak_up_spaces if fstr.last_spec && fstr.space
|
|
|
|
return final_result
|
|
end
|
|
|
|
private
|
|
|
|
def soak_up_spaces
|
|
c = getc
|
|
ungetc(c) if c
|
|
until eof ||! c || /\S/.match(c.chr)
|
|
c = getc
|
|
end
|
|
ungetc(c) if (c && /\S/.match(c.chr))
|
|
end
|
|
|
|
def block_scanf(str)
|
|
final = []
|
|
# Sub-ideal, since another FS gets created in scanf.
|
|
# But used here to determine the number of specifiers.
|
|
fstr = Scanf::FormatString.new(str)
|
|
last_spec = fstr.last_spec
|
|
begin
|
|
current = scanf(str)
|
|
break if current.empty?
|
|
final.push(yield(current))
|
|
end until eof || fstr.last_spec_tried == last_spec
|
|
return final
|
|
end
|
|
end
|
|
|
|
class String
|
|
|
|
# :section: scanf
|
|
#
|
|
# You will need to require 'scanf' to use these methods
|
|
|
|
# Scans the current string. If a block is given, it
|
|
# functions exactly like block_scanf.
|
|
#
|
|
# arr = "123 456".scanf("%d%d")
|
|
# # => [123, 456]
|
|
#
|
|
# require 'pp'
|
|
#
|
|
# "this 123 read that 456 other".scanf("%s%d%s") {|m| pp m}
|
|
#
|
|
# # ["this", 123, "read"]
|
|
# # ["that", 456, "other"]
|
|
# # => [["this", 123, "read"], ["that", 456, "other"]]
|
|
#
|
|
# See Scanf for details on creating a format string.
|
|
#
|
|
# You will need to require 'scanf' to use String#scanf
|
|
def scanf(fstr,&b) #:yield: current_match
|
|
if b
|
|
block_scanf(fstr,&b)
|
|
else
|
|
fs =
|
|
if fstr.is_a? Scanf::FormatString
|
|
fstr
|
|
else
|
|
Scanf::FormatString.new(fstr)
|
|
end
|
|
fs.match(self)
|
|
end
|
|
end
|
|
|
|
# Scans the current string until the match is exhausted
|
|
# yielding each match as it is encountered in the string.
|
|
# A block is not necessary as the results will simply
|
|
# be aggregated into the final array.
|
|
#
|
|
# "123 456".block_scanf("%d")
|
|
# # => [123, 456]
|
|
#
|
|
# If a block is given, the value from that is returned from
|
|
# the yield is added to an output array.
|
|
#
|
|
# "123 456".block_scanf("%d) do |digit,| # the ',' unpacks the Array
|
|
# digit + 100
|
|
# end
|
|
# # => [223, 556]
|
|
#
|
|
# See Scanf for details on creating a format string.
|
|
#
|
|
# You will need to require 'scanf' to use String#block_scanf
|
|
def block_scanf(fstr) #:yield: current_match
|
|
fs = Scanf::FormatString.new(fstr)
|
|
str = self.dup
|
|
final = []
|
|
begin
|
|
current = str.scanf(fs)
|
|
final.push(yield(current)) unless current.empty?
|
|
str = fs.string_left
|
|
end until current.empty? || str.empty?
|
|
return final
|
|
end
|
|
end
|
|
|
|
module Kernel
|
|
private
|
|
# Scans STDIN for data matching +format+. See IO#scanf for details.
|
|
#
|
|
# See Scanf for details on creating a format string.
|
|
#
|
|
# You will need to require 'scanf' to use Kernel#scanf.
|
|
def scanf(format, &b) #:doc:
|
|
STDIN.scanf(format ,&b)
|
|
end
|
|
end
|