Class: RE2::MatchData

Inherits:
Object show all
Defined in:
ext/re2/re2.cc

Instance Method Summary collapse

Instance Method Details

#[](index) ⇒ String? #[](start, length) ⇒ Array<String, nil> #[](range) ⇒ Array<String, nil> #[](name) ⇒ String?

Retrieve zero, one or more matches by index or name.

Note RE2 only supports UTF-8 and ISO-8859-1 encoding so strings will be returned in UTF-8 by default or ISO-8859-1 if the :utf8 option for the RE2::Regexp is set to false (any other encoding’s behaviour is undefined).

Overloads:

  • #[](index) ⇒ String?

    Access a particular match by index.

    Examples:

    m = RE2::Regexp.new('(\d+)').match("bob 123")
    m[0]    #=> "123"

    Parameters:

    • index (Integer)

      the index of the match to fetch

    Returns:

    • (String, nil)

      the specified match

  • #[](start, length) ⇒ Array<String, nil>

    Access a range of matches by starting index and length.

    Examples:

    m = RE2::Regexp.new('(\d+)').match("bob 123")
    m[0, 1]    #=> ["123"]

    Parameters:

    • start (Integer)

      the index from which to start

    • length (Integer)

      the number of elements to fetch

    Returns:

    • (Array<String, nil>)

      the specified matches

  • #[](range) ⇒ Array<String, nil>

    Access a range of matches by index.

    Examples:

    m = RE2::Regexp.new('(\d+)').match("bob 123")
    m[0..1]    #=> "[123", "123"]

    Parameters:

    • range (Range)

      the range of match indexes to fetch

    Returns:

    • (Array<String, nil>)

      the specified matches

  • #[](name) ⇒ String?

    Access a particular match by name.

    Examples:

    m = RE2::Regexp.new('(?P<number>\d+)').match("bob 123")
    m["number"] #=> "123"
    m[:number]  #=> "123"

    Parameters:

    • name (String, Symbol)

      the name of the match to fetch

    Returns:

    • (String, nil)

      the specific match

Returns:



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# File 'ext/re2/re2.cc', line 665

static VALUE re2_matchdata_aref(int argc, VALUE *argv, const VALUE self) {
  VALUE idx, rest;
  rb_scan_args(argc, argv, "11", &idx, &rest);

  if (TYPE(idx) == T_STRING) {
    return re2_matchdata_named_match(RSTRING_PTR(idx), self);
  } else if (SYMBOL_P(idx)) {
    return re2_matchdata_named_match(rb_id2name(SYM2ID(idx)), self);
  } else if (!NIL_P(rest) || !FIXNUM_P(idx) || FIX2INT(idx) < 0) {
    return rb_ary_aref(argc, argv, re2_matchdata_to_a(self));
  } else {
    return re2_matchdata_nth_match(FIX2INT(idx), self);
  }
}

#begin(n) ⇒ Integer

Returns the offset of the start of the nth element of the matchdata.

Examples:

m = RE2::Regexp.new('ob (\d+)').match("bob 123")
m.begin(0)  #=> 1
m.begin(1)  #=> 4

Parameters:

  • n (Integer, String, Symbol)

    the name or number of the match

Returns:

  • (Integer)

    the offset of the start of the match



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# File 'ext/re2/re2.cc', line 470

static VALUE re2_matchdata_begin(const VALUE self, VALUE n) {
  re2_matchdata *m;

  TypedData_Get_Struct(self, re2_matchdata, &re2_matchdata_data_type, m);

  re2::StringPiece *match = re2_matchdata_find_match(n, self);
  if (match == NULL) {
    return Qnil;
  } else {
    long offset = match->data() - RSTRING_PTR(m->text);

    return LONG2NUM(rb_str_sublen(m->text, offset));
  }
}

#deconstructArray<String, nil>

Returns the array of submatches for pattern matching.

Note RE2 only supports UTF-8 and ISO-8859-1 encoding so strings will be returned in UTF-8 by default or ISO-8859-1 if the :utf8 option for the RE2::Regexp is set to false (any other encoding’s behaviour is undefined).

Examples:

m = RE2::Regexp.new('(\d+)').match("bob 123")
m.deconstruct    #=> ["123"]

pattern matching

case RE2::Regexp.new('(\d+) (\d+)').match("bob 123 456")
in x, y
  puts "Matched #{x} #{y}"
else
  puts "Unrecognised match"
end

Returns:

  • (Array<String, nil>)

    the array of submatches



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# File 'ext/re2/re2.cc', line 753

static VALUE re2_matchdata_deconstruct(const VALUE self) {
  re2_matchdata *m;
  re2_pattern *p;

  TypedData_Get_Struct(self, re2_matchdata, &re2_matchdata_data_type, m);
  TypedData_Get_Struct(m->regexp, re2_pattern, &re2_regexp_data_type, p);

  VALUE array = rb_ary_new2(m->number_of_matches - 1);
  for (int i = 1; i < m->number_of_matches; ++i) {
    re2::StringPiece *match = &m->matches[i];

    if (match->empty()) {
      rb_ary_push(array, Qnil);
    } else {
      rb_ary_push(array, encoded_str_new(match->data(), match->size(),
            p->pattern->options().encoding()));
    }
  }

  return array;
}

#deconstruct_keys(keys) ⇒ Hash

Returns a hash of capturing group names to submatches for pattern matching.

As this is used by Ruby’s pattern matching, it will return an empty hash if given more keys than there are capturing groups. Given keys will populate the hash in order but an invalid name will cause the hash to be immediately returned.

Note RE2 only supports UTF-8 and ISO-8859-1 encoding so strings will be returned in UTF-8 by default or ISO-8859-1 if the :utf8 option for the RE2::Regexp is set to false (any other encoding’s behaviour is undefined).

Examples:

m = RE2::Regexp.new('(?P<numbers>\d+) (?P<letters>[a-zA-Z]+)').match('123 abc')
m.deconstruct_keys(nil)                  #=> {:numbers => "123", :letters => "abc"}
m.deconstruct_keys([:numbers])           #=> {:numbers => "123"}
m.deconstruct_keys([:fruit])             #=> {}
m.deconstruct_keys([:letters, :fruit])   #=> {:letters => "abc"}

pattern matching

case RE2::Regexp.new('(?P<numbers>\d+) (?P<letters>[a-zA-Z]+)').match('123 abc')
in numbers:, letters:
  puts "Numbers: #{numbers}, letters: #{letters}"
else
  puts "Unrecognised match"
end

Parameters:

  • keys (Array<Symbol>, nil)

    an array of Symbol capturing group names or nil to return all names

Returns:

  • (Hash)

    a hash of capturing group names to submatches



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# File 'ext/re2/re2.cc', line 803

static VALUE re2_matchdata_deconstruct_keys(const VALUE self, const VALUE keys) {
  re2_matchdata *m;
  re2_pattern *p;

  TypedData_Get_Struct(self, re2_matchdata, &re2_matchdata_data_type, m);
  TypedData_Get_Struct(m->regexp, re2_pattern, &re2_regexp_data_type, p);

  const std::map<std::string, int>& groups = p->pattern->NamedCapturingGroups();
  VALUE capturing_groups = rb_hash_new();

  if (NIL_P(keys)) {
    for (std::map<std::string, int>::const_iterator it = groups.begin(); it != groups.end(); ++it) {
      rb_hash_aset(capturing_groups,
          ID2SYM(rb_intern(it->first.data())),
          re2_matchdata_nth_match(it->second, self));
    }
  } else {
    Check_Type(keys, T_ARRAY);

    if (p->pattern->NumberOfCapturingGroups() >= RARRAY_LEN(keys)) {
      for (int i = 0; i < RARRAY_LEN(keys); ++i) {
        VALUE key = rb_ary_entry(keys, i);
        Check_Type(key, T_SYMBOL);
        const char *name = rb_id2name(SYM2ID(key));
        std::map<std::string, int>::const_iterator search = groups.find(name);

        if (search != groups.end()) {
          rb_hash_aset(capturing_groups, key, re2_matchdata_nth_match(search->second, self));
        } else {
          break;
        }
      }
    }
  }

  return capturing_groups;
}

#end(n) ⇒ Integer

Returns the offset of the character following the end of the nth element of the matchdata.

Examples:

m = RE2::Regexp.new('ob (\d+) b').match("bob 123 bob")
m.end(0)  #=> 9
m.end(1)  #=> 7

Parameters:

  • n (Integer, String, Symbol)

    the name or number of the match

Returns:

  • (Integer)

    the offset of the character following the end of the match



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# File 'ext/re2/re2.cc', line 495

static VALUE re2_matchdata_end(const VALUE self, VALUE n) {
  re2_matchdata *m;

  TypedData_Get_Struct(self, re2_matchdata, &re2_matchdata_data_type, m);

  re2::StringPiece *match = re2_matchdata_find_match(n, self);
  if (match == NULL) {
    return Qnil;
  } else {
    long offset = (match->data() - RSTRING_PTR(m->text)) + match->size();

    return LONG2NUM(rb_str_sublen(m->text, offset));
  }
}

#inspectString

Returns a printable version of the match.

Note RE2 only supports UTF-8 and ISO-8859-1 encoding so strings will be returned in UTF-8 by default or ISO-8859-1 if the :utf8 option for the RE2::Regexp is set to false (any other encoding’s behaviour is undefined).

Examples:

m = RE2::Regexp.new('(\d+)').match("bob 123")
m.inspect    #=> "#<RE2::MatchData \"123\" 1:\"123\">"

Returns:

  • (String)

    a printable version of the match



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# File 'ext/re2/re2.cc', line 701

static VALUE re2_matchdata_inspect(const VALUE self) {
  re2_matchdata *m;
  re2_pattern *p;

  TypedData_Get_Struct(self, re2_matchdata, &re2_matchdata_data_type, m);
  TypedData_Get_Struct(m->regexp, re2_pattern, &re2_regexp_data_type, p);

  std::ostringstream output;
  output << "#<RE2::MatchData";

  for (int i = 0; i < m->number_of_matches; ++i) {
    output << " ";

    if (i > 0) {
      output << i << ":";
    }

    VALUE match = re2_matchdata_nth_match(i, self);

    if (match == Qnil) {
      output << "nil";
    } else {
      output << "\"" << RSTRING_PTR(match) << "\"";
    }
  }

  output << ">";

  return encoded_str_new(output.str().data(), output.str().length(),
      p->pattern->options().encoding());
}

#lengthInteger

Returns the number of elements in the match array (including nils).

Examples:

m = RE2::Regexp.new('(\d+)').match("bob 123")
m.size      #=> 2
m.length    #=> 2

Returns:

  • (Integer)

    the number of elements



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# File 'ext/re2/re2.cc', line 452

static VALUE re2_matchdata_size(const VALUE self) {
  re2_matchdata *m;

  TypedData_Get_Struct(self, re2_matchdata, &re2_matchdata_data_type, m);

  return INT2FIX(m->number_of_matches);
}

#regexpRE2::Regexp

Returns the Regexp used in the match.

Examples:

m = RE2::Regexp.new('(\d+)').match("bob 123")
m.regexp    #=> #<RE2::Regexp /(\d+)/>

Returns:



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# File 'ext/re2/re2.cc', line 518

static VALUE re2_matchdata_regexp(const VALUE self) {
  re2_matchdata *m;
  TypedData_Get_Struct(self, re2_matchdata, &re2_matchdata_data_type, m);

  return m->regexp;
}

#sizeInteger

Returns the number of elements in the match array (including nils).

Examples:

m = RE2::Regexp.new('(\d+)').match("bob 123")
m.size      #=> 2
m.length    #=> 2

Returns:

  • (Integer)

    the number of elements



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# File 'ext/re2/re2.cc', line 452

static VALUE re2_matchdata_size(const VALUE self) {
  re2_matchdata *m;

  TypedData_Get_Struct(self, re2_matchdata, &re2_matchdata_data_type, m);

  return INT2FIX(m->number_of_matches);
}

#stringString

Returns a frozen copy of the string passed into match.

Examples:

m = RE2::Regexp.new('(\d+)').match("bob 123")
m.string  #=> "bob 123"

Returns:

  • (String)

    a frozen copy of the passed string.



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# File 'ext/re2/re2.cc', line 280

static VALUE re2_matchdata_string(const VALUE self) {
  re2_matchdata *m;
  TypedData_Get_Struct(self, re2_matchdata, &re2_matchdata_data_type, m);

  return m->text;
}

#to_aArray<String, nil>

Returns the array of matches.

Note RE2 only supports UTF-8 and ISO-8859-1 encoding so strings will be returned in UTF-8 by default or ISO-8859-1 if the :utf8 option for the RE2::Regexp is set to false (any other encoding’s behaviour is undefined).

Examples:

m = RE2::Regexp.new('(\d+)').match("bob 123")
m.to_a    #=> ["123", "123"]

Returns:

  • (Array<String, nil>)

    the array of matches



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# File 'ext/re2/re2.cc', line 558

static VALUE re2_matchdata_to_a(const VALUE self) {
  re2_matchdata *m;
  re2_pattern *p;

  TypedData_Get_Struct(self, re2_matchdata, &re2_matchdata_data_type, m);
  TypedData_Get_Struct(m->regexp, re2_pattern, &re2_regexp_data_type, p);

  VALUE array = rb_ary_new2(m->number_of_matches);
  for (int i = 0; i < m->number_of_matches; ++i) {
    re2::StringPiece *match = &m->matches[i];

    if (match->empty()) {
      rb_ary_push(array, Qnil);
    } else {
      rb_ary_push(array, encoded_str_new(match->data(), match->size(),
            p->pattern->options().encoding()));
    }
  }

  return array;
}

#to_sString

Returns the entire matched string.

Returns:

  • (String)

    the entire matched string



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# File 'ext/re2/re2.cc', line 685

static VALUE re2_matchdata_to_s(const VALUE self) {
  return re2_matchdata_nth_match(0, self);
}