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authorNorbert Preining <norbert@preining.info>2019-09-02 13:46:59 +0900
committerNorbert Preining <norbert@preining.info>2019-09-02 13:46:59 +0900
commite0c6872cf40896c7be36b11dcc744620f10adf1d (patch)
tree60335e10d2f4354b0674ec22d7b53f0f8abee672 /systems/texlive/tlnet/tlpkg/tlperl/lib/meta_notation.pm
Initial commit
Diffstat (limited to 'systems/texlive/tlnet/tlpkg/tlperl/lib/meta_notation.pm')
-rw-r--r--systems/texlive/tlnet/tlpkg/tlperl/lib/meta_notation.pm53
1 files changed, 53 insertions, 0 deletions
diff --git a/systems/texlive/tlnet/tlpkg/tlperl/lib/meta_notation.pm b/systems/texlive/tlnet/tlpkg/tlperl/lib/meta_notation.pm
new file mode 100644
index 0000000000..eea85875c9
--- /dev/null
+++ b/systems/texlive/tlnet/tlpkg/tlperl/lib/meta_notation.pm
@@ -0,0 +1,53 @@
+use strict;
+use warnings;
+
+# A tiny private library routine which is a helper to several Perl core
+# modules, to allow a paradigm to be implemented in a single place. The name,
+# contents, or even the existence of this file may be changed at any time and
+# are NOT to be used by anything outside the Perl core.
+
+sub _meta_notation ($) {
+
+ # Returns a copy of the input string with the nonprintable characters
+ # below 0x100 changed into printables. Any ASCII printables or above 0xFF
+ # are unchanged. (XXX Probably above-Latin1 characters should be
+ # converted to \X{...})
+ #
+ # \0 .. \x1F (which are "\c@" .. "\c_") are changed into ^@, ^A, ^B, ...
+ # ^Z, ^[, ^\, ^], ^^, ^_
+ # \c? is changed into ^?.
+ #
+ # The above accounts for all the ASCII-range nonprintables.
+ #
+ # On ASCII platforms, the upper-Latin1-range characters are converted to
+ # Meta notation, so that \xC1 becomes 'M-A', \xE2 becomes 'M-b', etc.
+ # This is how it always has worked, so is continued that way for backwards
+ # compatibility. The range \x80 .. \x9F becomes M-^@ .. M-^A, M-^B, ...
+ # M-^Z, M-^[, M-^\, M-^], M-^, M-^_
+ #
+ # On EBCDIC platforms, the upper-Latin1-range characters are converted
+ # into '\x{...}' Meta notation doesn't make sense on EBCDIC platforms
+ # because the ASCII-range printables are a mixture of upper bit set or
+ # not. [A-Za-Z0-9] all have the upper bit set. The underscore likely
+ # doesn't; and other punctuation may or may not. There's no simple
+ # pattern.
+
+ my $string = shift;
+
+ $string =~ s/([\0-\037])/
+ sprintf("^%c",utf8::unicode_to_native(ord($1)^64))/xeg;
+ $string =~ s/\c?/^?/g;
+ if (ord("A") == 65) {
+ $string =~ s/([\200-\237])/sprintf("M-^%c",(ord($1)&0177)^64)/eg;
+ $string =~ s/([\240-\377])/sprintf("M-%c" ,ord($1)&0177)/eg;
+ }
+ else {
+ no warnings 'experimental::regex_sets';
+ # Leave alone things above \xff
+ $string =~ s/( (?[ [\x00-\xFF] & [:^print:]])) /
+ sprintf("\\x{%X}", ord($1))/xaeg;
+ }
+
+ return $string;
+}
+1