类 MatchData
MatchData 封装了将 Regexp 与字符串匹配的结果。它由 Regexp#match 和 String#match 返回，并存储在由 Regexp.last_match 返回的全局变量中。
用法
url = 'https://docs.ruby-lang.org.cn/en/2.5.0/MatchData.html' m = url.match(/(\d\.?)+/) # => #<MatchData "2.5.0" 1:"0"> m.string # => "https://docs.ruby-lang.org.cn/en/2.5.0/MatchData.html" m.regexp # => /(\d\.?)+/ # entire matched substring: m[0] # => "2.5.0" # Working with unnamed captures m = url.match(%r{([^/]+)/([^/]+)\.html$}) m.captures # => ["2.5.0", "MatchData"] m[1] # => "2.5.0" m.values_at(1, 2) # => ["2.5.0", "MatchData"] # Working with named captures m = url.match(%r{(?<version>[^/]+)/(?<module>[^/]+)\.html$}) m.captures # => ["2.5.0", "MatchData"] m.named_captures # => {"version"=>"2.5.0", "module"=>"MatchData"} m[:version] # => "2.5.0" m.values_at(:version, :module) # => ["2.5.0", "MatchData"] # Numerical indexes are working, too m[1] # => "2.5.0" m.values_at(1, 2) # => ["2.5.0", "MatchData"]
全局变量等效性¶ ↑
最后一个 MatchData 的部分（由 Regexp.last_match 返回）也被别名为全局变量
-
$~是Regexp.last_match; -
$&是Regexp.last_match[ 0 ]; -
$1,$2等是Regexp.last_match[ i ]（按数字捕获）； -
$`是Regexp.last_match.pre_match; -
$'是Regexp.last_match.post_match; -
$+是Regexp.last_match[ -1 ]（最后一个捕获）。
另请参阅 Regexp 文档中的“特殊全局变量”部分。
公共实例方法
matchdata == object → true 或 false
如果 object 是另一个 MatchData 对象，其目标字符串、正则表达式、匹配和捕获与 self 相同，则返回 true，否则返回 false。
别名：eql?
matchdata[index] → string 或 nil 点击切换源代码
matchdata[start, length] → array
matchdata[range] → array
matchdata[name] → string 或 nil
当给出参数 index、+start 和 length 或 range 时，以 Array#[] 的风格返回匹配和捕获
m = /(.)(.)(\d+)(\d)/.match("THX1138.") # => #<MatchData "HX1138" 1:"H" 2:"X" 3:"113" 4:"8"> m[0] # => "HX1138" m[1, 2] # => ["H", "X"] m[1..3] # => ["H", "X", "113"] m[-3, 2] # => ["X", "113"]
当给出字符串或符号参数 name 时，返回给定名称的匹配子字符串
m = /(?<foo>.)(.)(?<bar>.+)/.match("hoge") # => #<MatchData "hoge" foo:"h" bar:"ge"> m['foo'] # => "h" m[:bar] # => "ge"
如果多个捕获具有相同的名称，则返回最后一个匹配的子字符串。
m = /(?<foo>.)(?<foo>.+)/.match("hoge") # => #<MatchData "hoge" foo:"h" foo:"oge"> m[:foo] #=> "oge" m = /\W(?<foo>.+)|\w(?<foo>.+)|(?<foo>.+)/.match("hoge") #<MatchData "hoge" foo:nil foo:"oge" foo:nil> m[:foo] #=> "oge"
static VALUE
match_aref(int argc, VALUE *argv, VALUE match)
{
VALUE idx, length;
match_check(match);
rb_scan_args(argc, argv, "11", &idx, &length);
if (NIL_P(length)) {
if (FIXNUM_P(idx)) {
return rb_reg_nth_match(FIX2INT(idx), match);
}
else {
int num = namev_to_backref_number(RMATCH_REGS(match), RMATCH(match)->regexp, idx);
if (num >= 0) {
return rb_reg_nth_match(num, match);
}
else {
return match_ary_aref(match, idx, Qnil);
}
}
}
else {
long beg = NUM2LONG(idx);
long len = NUM2LONG(length);
long num_regs = RMATCH_REGS(match)->num_regs;
if (len < 0) {
return Qnil;
}
if (beg < 0) {
beg += num_regs;
if (beg < 0) return Qnil;
}
else if (beg > num_regs) {
return Qnil;
}
if (beg+len > num_regs) {
len = num_regs - beg;
}
return match_ary_subseq(match, beg, len, Qnil);
}
}
begin(n) → integer 点击切换源代码
begin(name) → integer
返回指定匹配项开头的偏移量（以字符为单位）。
当给出非负整数参数 n 时，返回第 n 个匹配项开头的偏移量
m = /(.)(.)(\d+)(\d)/.match("THX1138.") # => #<MatchData "HX1138" 1:"H" 2:"X" 3:"113" 4:"8"> m[0] # => "HX1138" m.begin(0) # => 1 m[3] # => "113" m.begin(3) # => 3 m = /(т)(е)(с)/.match('тест') # => #<MatchData "тес" 1:"т" 2:"е" 3:"с"> m[0] # => "тес" m.begin(0) # => 0 m[3] # => "с" m.begin(3) # => 2
当给出字符串或符号参数 name 时，返回命名匹配项开头的偏移量
m = /(?<foo>.)(.)(?<bar>.)/.match("hoge") # => #<MatchData "hog" foo:"h" bar:"g"> m[:foo] # => "h" m.begin('foo') # => 0 m[:bar] # => "g" m.begin(:bar) # => 2
相关：MatchData#end，MatchData#offset，MatchData#byteoffset。
static VALUE
match_begin(VALUE match, VALUE n)
{
int i = match_backref_number(match, n);
struct re_registers *regs = RMATCH_REGS(match);
match_check(match);
backref_number_check(regs, i);
if (BEG(i) < 0)
return Qnil;
update_char_offset(match);
return LONG2NUM(RMATCH_EXT(match)->char_offset[i].beg);
}
byteoffset(n) → array 点击切换源代码
返回一个包含第 n 个匹配项的基于字节的开头和结尾偏移量的两个元素数组。n 可以是字符串或符号来引用命名捕获。
m = /(.)(.)(\d+)(\d)/.match("THX1138.") m.byteoffset(0) #=> [1, 7] m.byteoffset(4) #=> [6, 7] m = /(?<foo>.)(.)(?<bar>.)/.match("hoge") p m.byteoffset(:foo) #=> [0, 1] p m.byteoffset(:bar) #=> [2, 3]
static VALUE
match_byteoffset(VALUE match, VALUE n)
{
int i = match_backref_number(match, n);
struct re_registers *regs = RMATCH_REGS(match);
match_check(match);
backref_number_check(regs, i);
if (BEG(i) < 0)
return rb_assoc_new(Qnil, Qnil);
return rb_assoc_new(LONG2NUM(BEG(i)), LONG2NUM(END(i)));
}
captures → array 点击切换源代码
返回捕获数组，它们是除 m[0] 之外的所有匹配项
m = /(.)(.)(\d+)(\d)/.match("THX1138.") # => #<MatchData "HX1138" 1:"H" 2:"X" 3:"113" 4:"8"> m[0] # => "HX1138" m.captures # => ["H", "X", "113", "8"]
相关：MatchData.to_a。
static VALUE
match_captures(VALUE match)
{
return match_array(match, 1);
}
也称为：deconstruct
deconstruct()
返回捕获数组，它们是除 m[0] 之外的所有匹配项
m = /(.)(.)(\d+)(\d)/.match("THX1138.") # => #<MatchData "HX1138" 1:"H" 2:"X" 3:"113" 4:"8"> m[0] # => "HX1138" m.captures # => ["H", "X", "113", "8"]
相关：MatchData.to_a。
别名：captures
deconstruct_keys(array_of_names) → hash 点击切换源代码
返回给定名称的命名捕获的哈希表。
m = /(?<hours>\d{2}):(?<minutes>\d{2}):(?<seconds>\d{2})/.match("18:37:22") m.deconstruct_keys([:hours, :minutes]) # => {:hours => "18", :minutes => "37"} m.deconstruct_keys(nil) # => {:hours => "18", :minutes => "37", :seconds => "22"}
如果未定义命名捕获，则返回空哈希表
m = /(\d{2}):(\d{2}):(\d{2})/.match("18:37:22") m.deconstruct_keys(nil) # => {}
static VALUE
match_deconstruct_keys(VALUE match, VALUE keys)
{
VALUE h;
long i;
match_check(match);
if (NIL_P(RMATCH(match)->regexp)) {
return rb_hash_new_with_size(0);
}
if (NIL_P(keys)) {
h = rb_hash_new_with_size(onig_number_of_names(RREGEXP_PTR(RMATCH(match)->regexp)));
struct MEMO *memo;
memo = MEMO_NEW(h, match, 1);
onig_foreach_name(RREGEXP_PTR(RMATCH(match)->regexp), match_named_captures_iter, (void*)memo);
return h;
}
Check_Type(keys, T_ARRAY);
if (onig_number_of_names(RREGEXP_PTR(RMATCH(match)->regexp)) < RARRAY_LEN(keys)) {
return rb_hash_new_with_size(0);
}
h = rb_hash_new_with_size(RARRAY_LEN(keys));
for (i=0; i<RARRAY_LEN(keys); i++) {
VALUE key = RARRAY_AREF(keys, i);
VALUE name;
Check_Type(key, T_SYMBOL);
name = rb_sym2str(key);
int num = NAME_TO_NUMBER(RMATCH_REGS(match), RMATCH(match)->regexp, RMATCH(match)->regexp,
RSTRING_PTR(name), RSTRING_END(name));
if (num >= 0) {
rb_hash_aset(h, key, rb_reg_nth_match(num, match));
}
else {
return h;
}
}
return h;
}
end(n) → integer 点击切换源代码
end(name) → integer
返回指定匹配项结尾的偏移量（以字符为单位）。
当给出非负整数参数 n 时，返回第 n 个匹配项结尾的偏移量
m = /(.)(.)(\d+)(\d)/.match("THX1138.") # => #<MatchData "HX1138" 1:"H" 2:"X" 3:"113" 4:"8"> m[0] # => "HX1138" m.end(0) # => 7 m[3] # => "113" m.end(3) # => 6 m = /(т)(е)(с)/.match('тест') # => #<MatchData "тес" 1:"т" 2:"е" 3:"с"> m[0] # => "тес" m.end(0) # => 3 m[3] # => "с" m.end(3) # => 3
当给出字符串或符号参数 name 时，返回命名匹配项结尾的偏移量
m = /(?<foo>.)(.)(?<bar>.)/.match("hoge") # => #<MatchData "hog" foo:"h" bar:"g"> m[:foo] # => "h" m.end('foo') # => 1 m[:bar] # => "g" m.end(:bar) # => 3
相关：MatchData#begin，MatchData#offset，MatchData#byteoffset。
static VALUE
match_end(VALUE match, VALUE n)
{
int i = match_backref_number(match, n);
struct re_registers *regs = RMATCH_REGS(match);
match_check(match);
backref_number_check(regs, i);
if (BEG(i) < 0)
return Qnil;
update_char_offset(match);
return LONG2NUM(RMATCH_EXT(match)->char_offset[i].end);
}
eql? == object -> true or false 点击切换源代码
如果 object 是另一个 MatchData 对象，其目标字符串、正则表达式、匹配和捕获与 self 相同，则返回 true，否则返回 false。
static VALUE
match_equal(VALUE match1, VALUE match2)
{
const struct re_registers *regs1, *regs2;
if (match1 == match2) return Qtrue;
if (!RB_TYPE_P(match2, T_MATCH)) return Qfalse;
if (!RMATCH(match1)->regexp || !RMATCH(match2)->regexp) return Qfalse;
if (!rb_str_equal(RMATCH(match1)->str, RMATCH(match2)->str)) return Qfalse;
if (!rb_reg_equal(match_regexp(match1), match_regexp(match2))) return Qfalse;
regs1 = RMATCH_REGS(match1);
regs2 = RMATCH_REGS(match2);
if (regs1->num_regs != regs2->num_regs) return Qfalse;
if (memcmp(regs1->beg, regs2->beg, regs1->num_regs * sizeof(*regs1->beg))) return Qfalse;
if (memcmp(regs1->end, regs2->end, regs1->num_regs * sizeof(*regs1->end))) return Qfalse;
return Qtrue;
}
也称为：==
hash → integer 点击切换源代码
返回 self 的整数哈希值，基于目标字符串、正则表达式、匹配项和捕获。
另请参阅 Object#hash。
static VALUE
match_hash(VALUE match)
{
const struct re_registers *regs;
st_index_t hashval;
match_check(match);
hashval = rb_hash_start(rb_str_hash(RMATCH(match)->str));
hashval = rb_hash_uint(hashval, reg_hash(match_regexp(match)));
regs = RMATCH_REGS(match);
hashval = rb_hash_uint(hashval, regs->num_regs);
hashval = rb_hash_uint(hashval, rb_memhash(regs->beg, regs->num_regs * sizeof(*regs->beg)));
hashval = rb_hash_uint(hashval, rb_memhash(regs->end, regs->num_regs * sizeof(*regs->end)));
hashval = rb_hash_end(hashval);
return ST2FIX(hashval);
}
inspect → string 点击切换源代码
返回 self 的字符串表示形式。
m = /.$/.match("foo") # => #<MatchData "o"> m.inspect # => "#<MatchData \"o\">" m = /(.)(.)(.)/.match("foo") # => #<MatchData "foo" 1:"f" 2:"o" 3:"o"> m.inspect # => "#<MatchData \"foo\" 1:\"f\" 2:\"o\ m = /(.)(.)?(.)/.match("fo") # => #<MatchData "fo" 1:"f" 2:nil 3:"o"> m.inspect # => "#<MatchData \"fo\" 1:\"f\" 2:nil 3:\"o\">"
相关：MatchData#to_s.
static VALUE
match_inspect(VALUE match)
{
VALUE cname = rb_class_path(rb_obj_class(match));
VALUE str;
int i;
struct re_registers *regs = RMATCH_REGS(match);
int num_regs = regs->num_regs;
struct backref_name_tag *names;
VALUE regexp = RMATCH(match)->regexp;
if (regexp == 0) {
return rb_sprintf("#<%"PRIsVALUE":%p>", cname, (void*)match);
}
else if (NIL_P(regexp)) {
return rb_sprintf("#<%"PRIsVALUE": %"PRIsVALUE">",
cname, rb_reg_nth_match(0, match));
}
names = ALLOCA_N(struct backref_name_tag, num_regs);
MEMZERO(names, struct backref_name_tag, num_regs);
onig_foreach_name(RREGEXP_PTR(regexp),
match_inspect_name_iter, names);
str = rb_str_buf_new2("#<");
rb_str_append(str, cname);
for (i = 0; i < num_regs; i++) {
VALUE v;
rb_str_buf_cat2(str, " ");
if (0 < i) {
if (names[i].name)
rb_str_buf_cat(str, (const char *)names[i].name, names[i].len);
else {
rb_str_catf(str, "%d", i);
}
rb_str_buf_cat2(str, ":");
}
v = rb_reg_nth_match(i, match);
if (NIL_P(v))
rb_str_buf_cat2(str, "nil");
else
rb_str_buf_append(str, rb_str_inspect(v));
}
rb_str_buf_cat2(str, ">");
return str;
}
length()
返回匹配数组的大小。
m = /(.)(.)(\d+)(\d)/.match("THX1138.") # => #<MatchData "HX1138" 1:"H" 2:"X" 3:"113" 4:"8"> m.size # => 5
别名：size
match(n) → string or nil 点击切换源代码
match(name) → string or nil
返回与给定参数相对应的匹配子字符串。
当给出非负参数 n 时，返回第 n 个匹配的匹配子字符串。
m = /(.)(.)(\d+)(\d)(\w)?/.match("THX1138.") # => #<MatchData "HX1138" 1:"H" 2:"X" 3:"113" 4:"8" 5:nil> m.match(0) # => "HX1138" m.match(4) # => "8" m.match(5) # => nil
当给出字符串或符号参数 name 时，返回给定名称的匹配子字符串
m = /(?<foo>.)(.)(?<bar>.+)/.match("hoge") # => #<MatchData "hoge" foo:"h" bar:"ge"> m.match('foo') # => "h" m.match(:bar) # => "ge"
static VALUE
match_nth(VALUE match, VALUE n)
{
int i = match_backref_number(match, n);
struct re_registers *regs = RMATCH_REGS(match);
backref_number_check(regs, i);
long start = BEG(i), end = END(i);
if (start < 0)
return Qnil;
return rb_str_subseq(RMATCH(match)->str, start, end - start);
}
match_length(n) → integer or nil 点击切换源代码
match_length(name) → integer or nil
返回与给定参数相对应的匹配子字符串的长度（以字符为单位）。
当给出非负参数 n 时，返回第 n 个匹配的匹配子字符串的长度。
m = /(.)(.)(\d+)(\d)(\w)?/.match("THX1138.") # => #<MatchData "HX1138" 1:"H" 2:"X" 3:"113" 4:"8" 5:nil> m.match_length(0) # => 6 m.match_length(4) # => 1 m.match_length(5) # => nil
当给出字符串或符号参数 name 时，返回命名匹配的匹配子字符串的长度。
m = /(?<foo>.)(.)(?<bar>.+)/.match("hoge") # => #<MatchData "hoge" foo:"h" bar:"ge"> m.match_length('foo') # => 1 m.match_length(:bar) # => 2
static VALUE
match_nth_length(VALUE match, VALUE n)
{
int i = match_backref_number(match, n);
struct re_registers *regs = RMATCH_REGS(match);
match_check(match);
backref_number_check(regs, i);
if (BEG(i) < 0)
return Qnil;
update_char_offset(match);
const struct rmatch_offset *const ofs =
&RMATCH_EXT(match)->char_offset[i];
return LONG2NUM(ofs->end - ofs->beg);
}
named_captures(symbolize_names: false) → hash 点击切换源代码
返回命名捕获的哈希表；每个键都是捕获名称；每个值都是其捕获的字符串或 nil。
m = /(?<foo>.)(.)(?<bar>.+)/.match("hoge") # => #<MatchData "hoge" foo:"h" bar:"ge"> m.named_captures # => {"foo"=>"h", "bar"=>"ge"} m = /(?<a>.)(?<b>.)/.match("01") # => #<MatchData "01" a:"0" b:"1"> m.named_captures #=> {"a" => "0", "b" => "1"} m = /(?<a>.)(?<b>.)?/.match("0") # => #<MatchData "0" a:"0" b:nil> m.named_captures #=> {"a" => "0", "b" => nil} m = /(?<a>.)(?<a>.)/.match("01") # => #<MatchData "01" a:"0" a:"1"> m.named_captures #=> {"a" => "1"}
如果关键字参数 symbolize_names 给出了真值，则结果哈希表中的键是符号。
m = /(?<a>.)(?<a>.)/.match("01") # => #<MatchData "01" a:"0" a:"1"> m.named_captures(symbolize_names: true) #=> {:a => "1"}
static VALUE
match_named_captures(int argc, VALUE *argv, VALUE match)
{
VALUE hash;
struct MEMO *memo;
match_check(match);
if (NIL_P(RMATCH(match)->regexp))
return rb_hash_new();
VALUE opt;
VALUE symbolize_names = 0;
rb_scan_args(argc, argv, "0:", &opt);
if (!NIL_P(opt)) {
static ID keyword_ids[1];
VALUE symbolize_names_val;
if (!keyword_ids[0]) {
keyword_ids[0] = rb_intern_const("symbolize_names");
}
rb_get_kwargs(opt, keyword_ids, 0, 1, &symbolize_names_val);
if (!UNDEF_P(symbolize_names_val) && RTEST(symbolize_names_val)) {
symbolize_names = 1;
}
}
hash = rb_hash_new();
memo = MEMO_NEW(hash, match, symbolize_names);
onig_foreach_name(RREGEXP(RMATCH(match)->regexp)->ptr, match_named_captures_iter, (void*)memo);
return hash;
}
names → array_of_names 点击切换源代码
返回捕获名称的数组（参见 命名捕获）。
m = /(?<foo>.)(?<bar>.)(?<baz>.)/.match("hoge") # => #<MatchData "hog" foo:"h" bar:"o" baz:"g"> m.names # => ["foo", "bar", "baz"] m = /foo/.match('foo') # => #<MatchData "foo"> m.names # => [] # No named captures.
等效于
m = /(?<foo>.)(?<bar>.)(?<baz>.)/.match("hoge") m.regexp.names # => ["foo", "bar", "baz"]
static VALUE
match_names(VALUE match)
{
match_check(match);
if (NIL_P(RMATCH(match)->regexp))
return rb_ary_new_capa(0);
return rb_reg_names(RMATCH(match)->regexp);
}
offset(n) → [start_offset, end_offset] 点击切换源代码
offset(name) → [start_offset, end_offset]
返回一个包含指定匹配的开始和结束偏移量（以字符为单位）的 2 元素数组。
当给出非负整数参数 n 时，返回第 n 个匹配的开始和结束偏移量。
m = /(.)(.)(\d+)(\d)/.match("THX1138.") # => #<MatchData "HX1138" 1:"H" 2:"X" 3:"113" 4:"8"> m[0] # => "HX1138" m.offset(0) # => [1, 7] m[3] # => "113" m.offset(3) # => [3, 6] m = /(т)(е)(с)/.match('тест') # => #<MatchData "тес" 1:"т" 2:"е" 3:"с"> m[0] # => "тес" m.offset(0) # => [0, 3] m[3] # => "с" m.offset(3) # => [2, 3]
当给出字符串或符号参数 name 时，返回命名匹配的开始和结束偏移量。
m = /(?<foo>.)(.)(?<bar>.)/.match("hoge") # => #<MatchData "hog" foo:"h" bar:"g"> m[:foo] # => "h" m.offset('foo') # => [0, 1] m[:bar] # => "g" m.offset(:bar) # => [2, 3]
相关：MatchData#byteoffset，MatchData#begin，MatchData#end。
static VALUE
match_offset(VALUE match, VALUE n)
{
int i = match_backref_number(match, n);
struct re_registers *regs = RMATCH_REGS(match);
match_check(match);
backref_number_check(regs, i);
if (BEG(i) < 0)
return rb_assoc_new(Qnil, Qnil);
update_char_offset(match);
return rb_assoc_new(LONG2NUM(RMATCH_EXT(match)->char_offset[i].beg),
LONG2NUM(RMATCH_EXT(match)->char_offset[i].end));
}
post_match → str 点击切换源代码
返回目标字符串中从self中第一个匹配项（即self[0]）的末尾到字符串末尾的子字符串；等效于正则表达式全局变量$'
m = /(.)(.)(\d+)(\d)/.match("THX1138: The Movie") # => #<MatchData "HX1138" 1:"H" 2:"X" 3:"113" 4:"8"> m[0] # => "HX1138" m.post_match # => ": The Movie"\
VALUE
rb_reg_match_post(VALUE match)
{
VALUE str;
long pos;
struct re_registers *regs;
if (NIL_P(match)) return Qnil;
match_check(match);
regs = RMATCH_REGS(match);
if (BEG(0) == -1) return Qnil;
str = RMATCH(match)->str;
pos = END(0);
str = rb_str_subseq(str, pos, RSTRING_LEN(str) - pos);
return str;
}
pre_match → string 点击切换源代码
返回目标字符串中从其开头到self中第一个匹配项（即self[0]）的子字符串；等效于正则表达式全局变量$`
m = /(.)(.)(\d+)(\d)/.match("THX1138.") # => #<MatchData "HX1138" 1:"H" 2:"X" 3:"113" 4:"8"> m[0] # => "HX1138" m.pre_match # => "T"
VALUE
rb_reg_match_pre(VALUE match)
{
VALUE str;
struct re_registers *regs;
if (NIL_P(match)) return Qnil;
match_check(match);
regs = RMATCH_REGS(match);
if (BEG(0) == -1) return Qnil;
str = rb_str_subseq(RMATCH(match)->str, 0, BEG(0));
return str;
}
regexp → regexp 点击切换源代码
返回产生匹配的正则表达式
m = /a.*b/.match("abc") # => #<MatchData "ab"> m.regexp # => /a.*b/
static VALUE
match_regexp(VALUE match)
{
VALUE regexp;
match_check(match);
regexp = RMATCH(match)->regexp;
if (NIL_P(regexp)) {
VALUE str = rb_reg_nth_match(0, match);
regexp = rb_reg_regcomp(rb_reg_quote(str));
RB_OBJ_WRITE(match, &RMATCH(match)->regexp, regexp);
}
return regexp;
}
size → integer 点击切换源代码
返回匹配数组的大小。
m = /(.)(.)(\d+)(\d)/.match("THX1138.") # => #<MatchData "HX1138" 1:"H" 2:"X" 3:"113" 4:"8"> m.size # => 5
static VALUE
match_size(VALUE match)
{
match_check(match);
return INT2FIX(RMATCH_REGS(match)->num_regs);
}
也称为：length
string → string 点击切换源代码
如果目标字符串被冻结，则返回目标字符串；否则，返回目标字符串的冻结副本
m = /(.)(.)(\d+)(\d)/.match("THX1138.") # => #<MatchData "HX1138" 1:"H" 2:"X" 3:"113" 4:"8"> m.string # => "THX1138."
static VALUE
match_string(VALUE match)
{
match_check(match);
return RMATCH(match)->str; /* str is frozen */
}
to_a → array 点击切换源代码
返回匹配项的数组
m = /(.)(.)(\d+)(\d)/.match("THX1138.") # => #<MatchData "HX1138" 1:"H" 2:"X" 3:"113" 4:"8"> m.to_a # => ["HX1138", "H", "X", "113", "8"]
static VALUE
match_to_a(VALUE match)
{
return match_array(match, 0);
}
to_s → string 点击切换源代码
返回匹配的字符串
m = /(.)(.)(\d+)(\d)/.match("THX1138.") # => #<MatchData "HX1138" 1:"H" 2:"X" 3:"113" 4:"8"> m.to_s # => "HX1138" m = /(?<foo>.)(.)(?<bar>.+)/.match("hoge") # => #<MatchData "hoge" foo:"h" bar:"ge"> m.to_s # => "hoge"
static VALUE
match_to_s(VALUE match)
{
VALUE str = rb_reg_last_match(match_check(match));
if (NIL_P(str)) str = rb_str_new(0,0);
return str;
}
values_at(*indexes) → array 点击切换源代码
返回给定indexes处的匹配项和捕获项，这些indexes可以包含任何混合的
-
整数。
-
范围。
-
名称（字符串和符号）。
示例
m = /(.)(.)(\d+)(\d)/.match("THX1138: The Movie") # => #<MatchData "HX1138" 1:"H" 2:"X" 3:"113" 4:"8"> m.values_at(0, 2, -2) # => ["HX1138", "X", "113"] m.values_at(1..2, -1) # => ["H", "X", "8"] m = /(?<a>\d+) *(?<op>[+\-*\/]) *(?<b>\d+)/.match("1 + 2") # => #<MatchData "1 + 2" a:"1" op:"+" b:"2"> m.values_at(0, 1..2, :a, :b, :op) # => ["1 + 2", "1", "+", "1", "2", "+"]
static VALUE
match_values_at(int argc, VALUE *argv, VALUE match)
{
VALUE result;
int i;
match_check(match);
result = rb_ary_new2(argc);
for (i=0; i<argc; i++) {
if (FIXNUM_P(argv[i])) {
rb_ary_push(result, rb_reg_nth_match(FIX2INT(argv[i]), match));
}
else {
int num = namev_to_backref_number(RMATCH_REGS(match), RMATCH(match)->regexp, argv[i]);
if (num >= 0) {
rb_ary_push(result, rb_reg_nth_match(num, match));
}
else {
match_ary_aref(match, argv[i], result);
}
}
}
return result;
}