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25
26## -*- texinfo -*-
27## @deftypefn {} {} regexptranslate (@var{op}, @var{s})
28## Translate a string for use in a regular expression.
29##
30## This may include either wildcard replacement or special character escaping.
31##
32## The behavior is controlled by @var{op} which can take the following
33## values
34##
35## @table @asis
36## @item @qcode{"wildcard"}
37## The wildcard characters @code{.}, @code{*}, and @code{?} are replaced with
38## wildcards that are appropriate for a regular expression.  For example:
39##
40## @example
41## @group
42## regexptranslate ("wildcard", "*.m")
43##      @result{} '.*\.m'
44## @end group
45## @end example
46##
47## @item @qcode{"escape"}
48## The characters @code{$.?[]}, that have special meaning for regular
49## expressions are escaped so that they are treated literally.  For example:
50##
51## @example
52## @group
53## regexptranslate ("escape", "12.5")
54##      @result{} '12\.5'
55## @end group
56## @end example
57##
58## @end table
59## @seealso{regexp, regexpi, regexprep}
60## @end deftypefn
61
62function y = regexptranslate (op, s)
63
64  if (nargin != 2)
65    print_usage ();
66  endif
67
68  if (! ischar (op))
69    error ("regexptranslate: operation OP must be a string");
70  endif
71
72  op = tolower (op);
73  if (strcmp ("wildcard", op))
74    y = strrep (strrep (strrep (s, '.', '\.'),
75                                   '*', '.*'),
76                                   '?', '.');
77  elseif (strcmp ("escape", op))
78    y = regexprep (s, '([][(){}.*+?^$|\\])', '\\$1');
79  else
80    error ("regexptranslate: invalid operation OP");
81  endif
82
83endfunction
84
85
86%!assert (regexptranslate ("wildcard", "/a*b?c."), "/a.*b.c\\.")
87%!assert (regexptranslate ("escape", '^.?[abc]$'), '\^\.\?\[abc\]\$')
88
89## Test input validation
90%!error <Invalid call to regexptranslate> regexptranslate ()
91%!error <Invalid call to regexptranslate> regexptranslate ("wildcard")
92%!error <Invalid call to regexptranslate> regexptranslate ("a", "b", "c")
93%!error <invalid operation> regexptranslate ("foo", "abc")
94%!error <operation OP must be a string> regexptranslate (10, "abc")
95