* libguile/read.c (scm_read_string): Return a freshly allocated string
every time, even for empty strings. The motivation is to allow source
properties to be added to all strings. Previously, the shared global
'scm_nullstr' was returned for empty strings. Note that empty strings
still share a common global 'null_stringbuf'.
* test-suite/tests/srfi-13.test (substring/shared): Fix tests to reflect
the fact that empty string literals are no longer guaranteed to be
'eq?' to each other.
* doc/ref/api-data.texi (Characters): Documentation for `char-titlecase'.
* doc/ref/api-i18n.texi (Character Case Mapping): Documentation for
`char-locale-titlecase' and `string-locale-titlecase'.
* libguile/chars.c, libguile/chars.h (scm_char_titlecase, scm_c_titlecase): New
functions.
* libguile/i18n.c, libguile/i18n.h (chr_to_case, scm_char_locale_titlecase,
str_to_case, scm_string_locale_titlecase): New functions.
* libguile/i18n.c (scm_char_locale_downcase, scm_char_locale_upcase,
scm_string_locale_downcase, scm_string_locale_upcase): Refactor to share code
via chr_to_case and str_to_case, as appropriate.
* module/ice-9/i18n.scm (char-locale-title-case, string-locale-titlecase): New
functions.
* libguile/srfi-13.c (string_titlecase_x): Use uc_totitle instead of uc_toupper.
* test-suite/tests/chars.test: Tests for `char-titlecase'.
* test-suite/tests/i18n.test: Tests for `char-locale-titlecase' and
`string-locale-titlecase'.
* test-suite/tests/srfi-13.test: Tests for `string-titlecase'.
* test-suite/tests/vectors.test: test make-vector and interactions between
strings and vectors
* test-suite/tests/strings.test: test string-null?, string? and backslash
escapes
* test-suite/tests/srfi-13.test: test null input strings in string-any and
string-every
proc args to conform with the srfi. (Thanks to Alex Shinn.)
* srfi-13.c (string-map): Swapped order of string and proc args to
conform with the srfi. (Thanks to Alex Shinn.)
