diff options
| author | Vance Shipley <[email protected]> | 2012-04-04 18:17:33 +0530 |
|---|---|---|
| committer | Henrik Nord <[email protected]> | 2012-07-10 14:58:54 +0200 |
| commit | 264e667b86381528131c45c9b6e8f54ad168c73f (patch) | |
| tree | 9e13064162e668b38ffc867de62350e92336e93a | |
| parent | c075ac6484e3d5a93a0d870ab4483d39ae26eaec (diff) | |
| download | otp-264e667b86381528131c45c9b6e8f54ad168c73f.tar.gz otp-264e667b86381528131c45c9b6e8f54ad168c73f.tar.bz2 otp-264e667b86381528131c45c9b6e8f54ad168c73f.zip | |
extend re back reference syntax with \g escape sequence
Add the \gN and \g{N} syntax for back references in re:replace/3,4
to allow use with numeric replacement strings.
| -rw-r--r-- | lib/stdlib/doc/src/re.xml | 4 | ||||
| -rw-r--r-- | lib/stdlib/src/re.erl | 6 | ||||
| -rw-r--r-- | lib/stdlib/test/re_SUITE.erl | 6 |
3 files changed, 14 insertions, 2 deletions
diff --git a/lib/stdlib/doc/src/re.xml b/lib/stdlib/doc/src/re.xml index 6d5336796c..224b4b2771 100644 --- a/lib/stdlib/doc/src/re.xml +++ b/lib/stdlib/doc/src/re.xml @@ -524,8 +524,8 @@ This option makes it possible to include comments inside complicated patterns. N <p>The replacement string can contain the special character <c>&</c>, which inserts the whole matching expression in the - result, and the special sequence <c>\</c>N (where N is an - integer > 0), resulting in the subexpression number N will be + result, and the special sequence <c>\</c>N (where N is an integer > 0), + <c>\g</c>N or <c>\g{</c>N<c>}</c> resulting in the subexpression number N will be inserted in the result. If no subexpression with that number is generated by the regular expression, nothing is inserted.</p> <p>To insert an <c>&</c> or <c>\</c> in the result, precede it diff --git a/lib/stdlib/src/re.erl b/lib/stdlib/src/re.erl index 246d535943..70566e48dd 100644 --- a/lib/stdlib/src/re.erl +++ b/lib/stdlib/src/re.erl @@ -355,6 +355,12 @@ apply_mlist(Subject,Replacement,Mlist) -> precomp_repl(<<>>) -> []; +precomp_repl(<<$\\,$g,${,Rest/binary>>) when byte_size(Rest) > 0 -> + {NS, <<$},NRest/binary>>} = pick_int(Rest), + [list_to_integer(NS) | precomp_repl(NRest)]; +precomp_repl(<<$\\,$g,Rest/binary>>) when byte_size(Rest) > 0 -> + {NS,NRest} = pick_int(Rest), + [list_to_integer(NS) | precomp_repl(NRest)]; precomp_repl(<<$\\,X,Rest/binary>>) when X < $1 ; X > $9 -> %% Escaped character case precomp_repl(Rest) of diff --git a/lib/stdlib/test/re_SUITE.erl b/lib/stdlib/test/re_SUITE.erl index a542745e67..8ee0a13f4c 100644 --- a/lib/stdlib/test/re_SUITE.erl +++ b/lib/stdlib/test/re_SUITE.erl @@ -328,6 +328,12 @@ replace_return(Config) when is_list(Config) -> ?line <<"iXk">> = re:replace("abcdefghijk","(.)(.)(.)(.)(.)(.)(.)(.)(.)(.)","\\9X",[{return,binary}]), ?line <<"jXk">> = re:replace("abcdefghijk","(.)(.)(.)(.)(.)(.)(.)(.)(.)(.)","\\10X",[{return,binary}]), ?line <<"Xk">> = re:replace("abcdefghijk","(.)(.)(.)(.)(.)(.)(.)(.)(.)(.)","\\11X",[{return,binary}]), + ?line <<"9X1">> = re:replace("12345678901","(.)(.)(.)(.)(.)(.)(.)(.)(.)(.)","\\g9X",[{return,binary}]), + ?line <<"0X1">> = re:replace("12345678901","(.)(.)(.)(.)(.)(.)(.)(.)(.)(.)","\\g10X",[{return,binary}]), + ?line <<"X1">> = re:replace("12345678901","(.)(.)(.)(.)(.)(.)(.)(.)(.)(.)","\\g11X",[{return,binary}]), + ?line <<"971">> = re:replace("12345678901","(.)(.)(.)(.)(.)(.)(.)(.)(.)(.)","\\g{9}7",[{return,binary}]), + ?line <<"071">> = re:replace("12345678901","(.)(.)(.)(.)(.)(.)(.)(.)(.)(.)","\\g{10}7",[{return,binary}]), + ?line <<"71">> = re:replace("12345678901","(.)(.)(.)(.)(.)(.)(.)(.)(.)(.)","\\g{11}7",[{return,binary}]), ?line "a\x{400}bcX" = re:replace("a\x{400}bcd","d","X",[global,{return,list},unicode]), ?line <<"a",208,128,"bcX">> = re:replace("a\x{400}bcd","d","X",[global,{return,binary},unicode]), ?line "a\x{400}bcd" = re:replace("a\x{400}bcd","Z","X",[global,{return,list},unicode]), |