If you know the name of a scalar variable, you can get a pointer to its SV
by using the following:
- SV* get_sv("package::varname", FALSE);
+ SV* get_sv("package::varname", 0);
This returns NULL if the variable does not exist.
C<AvARRAY> points to the first element in the array that is visible from
Perl, C<AvALLOC> points to the real start of the C array. These are
usually the same, but a C<shift> operation can be carried out by
-increasing C<AvARRAY> by one and decreasing C<AvFILL> and C<AvLEN>.
+increasing C<AvARRAY> by one and decreasing C<AvFILL> and C<AvMAX>.
Again, the location of the real start of the C array only comes into
play when freeing the array. See C<av_shift> in F<av.c>.
If you know the name of an array variable, you can get a pointer to its AV
by using the following:
- AV* get_av("package::varname", FALSE);
+ AV* get_av("package::varname", 0);
This returns NULL if the variable does not exist.
If you know the name of a hash variable, you can get a pointer to its HV
by using the following:
- HV* get_hv("package::varname", FALSE);
+ HV* get_hv("package::varname", 0);
This returns NULL if the variable does not exist.
SVt_PVGV Glob (possible a file handle)
SVt_PVMG Blessed or Magical Scalar
- See the sv.h header file for more details.
+See the F<sv.h> header file for more details.
=head2 Blessed References and Class Objects
To create a new Perl variable with an undef value which can be accessed from
your Perl script, use the following routines, depending on the variable type.
- SV* get_sv("package::varname", TRUE);
- AV* get_av("package::varname", TRUE);
- HV* get_hv("package::varname", TRUE);
+ SV* get_sv("package::varname", GV_ADD);
+ AV* get_av("package::varname", GV_ADD);
+ HV* get_hv("package::varname", GV_ADD);
Notice the use of TRUE as the second parameter. The new variable can now
be set, using the routines appropriate to the data type.
If you are not sure then doing an C<SvREFCNT_inc> and C<sv_2mortal>, or
making a C<sv_mortalcopy> is safer.
-The mortal routines are not just for SVs -- AVs and HVs can be
+The mortal routines are not just for SVs; AVs and HVs can be
made mortal by passing their address (type-casted to C<SV*>) to the
C<sv_2mortal> or C<sv_mortalcopy> routines.
To get the stash pointer for a particular package, use the function:
- HV* gv_stashpv(const char* name, I32 create)
- HV* gv_stashsv(SV*, I32 create)
+ HV* gv_stashpv(const char* name, I32 flags)
+ HV* gv_stashsv(SV*, I32 flags)
The first function takes a literal string, the second uses the string stored
in the SV. Remember that a stash is just a hash table, so you get back an
-C<HV*>. The C<create> flag will create a new package if it is set.
+C<HV*>. The C<flags> flag will create a new package if it is set to GV_ADD.
The name that C<gv_stash*v> wants is the name of the package whose symbol table
you want. The default package is called C<main>. If you have multiply nested
extern int dberror;
extern char *dberror_list;
- SV* sv = get_sv("dberror", TRUE);
+ SV* sv = get_sv("dberror", GV_ADD);
sv_setiv(sv, (IV) dberror);
sv_setpv(sv, dberror_list[dberror]);
SvIOK_on(sv);
U16 mg_private;
char mg_type;
U8 mg_flags;
+ I32 mg_len;
SV* mg_obj;
char* mg_ptr;
- I32 mg_len;
};
Note this is current as of patchlevel 0, and could change at any time.
int (*svt_clear)(SV* sv, MAGIC* mg);
int (*svt_free)(SV* sv, MAGIC* mg);
- int (*svt_copy)(SV *sv, MAGIC* mg, SV *nsv, const char *name, int namlen);
+ int (*svt_copy)(SV *sv, MAGIC* mg, SV *nsv, const char *name, I32 namlen);
int (*svt_dup)(MAGIC *mg, CLONE_PARAMS *param);
int (*svt_local)(SV *nsv, MAGIC *mg);
This MGVTBL structure is set at compile-time in F<perl.h> and there are
-currently 19 types (or 21 with overloading turned on). These different
-structures contain pointers to various routines that perform additional
-actions depending on which function is being called.
+currently 32 types. These different structures contain pointers to various
+routines that perform additional actions depending on which function is
+being called.
Function pointer Action taken
---------------- ------------
svt_get Do something before the value of the SV is retrieved.
svt_set Do something after the SV is assigned a value.
svt_len Report on the SV's length.
- svt_clear Clear something the SV represents.
+ svt_clear Clear something the SV represents.
svt_free Free any extra storage associated with the SV.
- svt_copy copy tied variable magic to a tied element
- svt_dup duplicate a magic structure during thread cloning
- svt_local copy magic to local value during 'local'
+ svt_copy copy tied variable magic to a tied element
+ svt_dup duplicate a magic structure during thread cloning
+ svt_local copy magic to local value during 'local'
For instance, the MGVTBL structure called C<vtbl_sv> (which corresponds
to an C<mg_type> of C<PERL_MAGIC_sv>) contains:
The current kinds of Magic Virtual Tables are:
mg_type
- (old-style char and macro) MGVTBL Type of magic
- -------------------------- ------ ----------------------------
- \0 PERL_MAGIC_sv vtbl_sv Special scalar variable
- A PERL_MAGIC_overload vtbl_amagic %OVERLOAD hash
+ (old-style char and macro) MGVTBL Type of magic
+ -------------------------- ------ -------------
+ \0 PERL_MAGIC_sv vtbl_sv Special scalar variable
+ A PERL_MAGIC_overload vtbl_amagic %OVERLOAD hash
a PERL_MAGIC_overload_elem vtbl_amagicelem %OVERLOAD hash element
- c PERL_MAGIC_overload_table (none) Holds overload table (AMT)
- on stash
- B PERL_MAGIC_bm vtbl_bm Boyer-Moore (fast string search)
- D PERL_MAGIC_regdata vtbl_regdata Regex match position data
- (@+ and @- vars)
- d PERL_MAGIC_regdatum vtbl_regdatum Regex match position data
- element
- E PERL_MAGIC_env vtbl_env %ENV hash
- e PERL_MAGIC_envelem vtbl_envelem %ENV hash element
- f PERL_MAGIC_fm vtbl_fm Formline ('compiled' format)
- g PERL_MAGIC_regex_global vtbl_mglob m//g target / study()ed string
- H PERL_MAGIC_hints vtbl_sig %^H hash
- h PERL_MAGIC_hintselem vtbl_hintselem %^H hash element
- I PERL_MAGIC_isa vtbl_isa @ISA array
- i PERL_MAGIC_isaelem vtbl_isaelem @ISA array element
- k PERL_MAGIC_nkeys vtbl_nkeys scalar(keys()) lvalue
- L PERL_MAGIC_dbfile (none) Debugger %_<filename
- l PERL_MAGIC_dbline vtbl_dbline Debugger %_<filename element
- m PERL_MAGIC_mutex vtbl_mutex ???
- o PERL_MAGIC_collxfrm vtbl_collxfrm Locale collate transformation
- P PERL_MAGIC_tied vtbl_pack Tied array or hash
- p PERL_MAGIC_tiedelem vtbl_packelem Tied array or hash element
- q PERL_MAGIC_tiedscalar vtbl_packelem Tied scalar or handle
- r PERL_MAGIC_qr vtbl_qr precompiled qr// regex
- S PERL_MAGIC_sig vtbl_sig %SIG hash
- s PERL_MAGIC_sigelem vtbl_sigelem %SIG hash element
- t PERL_MAGIC_taint vtbl_taint Taintedness
- U PERL_MAGIC_uvar vtbl_uvar Available for use by extensions
- v PERL_MAGIC_vec vtbl_vec vec() lvalue
- V PERL_MAGIC_vstring (none) v-string scalars
- w PERL_MAGIC_utf8 vtbl_utf8 UTF-8 length+offset cache
- x PERL_MAGIC_substr vtbl_substr substr() lvalue
- y PERL_MAGIC_defelem vtbl_defelem Shadow "foreach" iterator
- variable / smart parameter
- vivification
- # PERL_MAGIC_arylen vtbl_arylen Array length ($#ary)
- . PERL_MAGIC_pos vtbl_pos pos() lvalue
- < PERL_MAGIC_backref vtbl_backref back pointer to a weak ref
- ~ PERL_MAGIC_ext (none) Available for use by extensions
- : PERL_MAGIC_symtab (none) hash used as symbol table
- % PERL_MAGIC_rhash (none) hash used as restricted hash
- @ PERL_MAGIC_arylen_p vtbl_arylen_p pointer to $#a from @a
+ c PERL_MAGIC_overload_table (none) Holds overload table (AMT)
+ on stash
+ B PERL_MAGIC_bm vtbl_bm Boyer-Moore (fast string search)
+ D PERL_MAGIC_regdata vtbl_regdata Regex match position data
+ (@+ and @- vars)
+ d PERL_MAGIC_regdatum vtbl_regdatum Regex match position data
+ element
+ E PERL_MAGIC_env vtbl_env %ENV hash
+ e PERL_MAGIC_envelem vtbl_envelem %ENV hash element
+ f PERL_MAGIC_fm vtbl_fm Formline ('compiled' format)
+ g PERL_MAGIC_regex_global vtbl_mglob m//g target / study()ed string
+ H PERL_MAGIC_hints vtbl_hints %^H hash
+ h PERL_MAGIC_hintselem vtbl_hintselem %^H hash element
+ I PERL_MAGIC_isa vtbl_isa @ISA array
+ i PERL_MAGIC_isaelem vtbl_isaelem @ISA array element
+ k PERL_MAGIC_nkeys vtbl_nkeys scalar(keys()) lvalue
+ L PERL_MAGIC_dbfile (none) Debugger %_<filename
+ l PERL_MAGIC_dbline vtbl_dbline Debugger %_<filename element
+ o PERL_MAGIC_collxfrm vtbl_collxfrm Locale collate transformation
+ P PERL_MAGIC_tied vtbl_pack Tied array or hash
+ p PERL_MAGIC_tiedelem vtbl_packelem Tied array or hash element
+ q PERL_MAGIC_tiedscalar vtbl_packelem Tied scalar or handle
+ r PERL_MAGIC_qr vtbl_qr precompiled qr// regex
+ S PERL_MAGIC_sig vtbl_sig %SIG hash
+ s PERL_MAGIC_sigelem vtbl_sigelem %SIG hash element
+ t PERL_MAGIC_taint vtbl_taint Taintedness
+ U PERL_MAGIC_uvar vtbl_uvar Available for use by extensions
+ v PERL_MAGIC_vec vtbl_vec vec() lvalue
+ V PERL_MAGIC_vstring (none) v-string scalars
+ w PERL_MAGIC_utf8 vtbl_utf8 UTF-8 length+offset cache
+ x PERL_MAGIC_substr vtbl_substr substr() lvalue
+ y PERL_MAGIC_defelem vtbl_defelem Shadow "foreach" iterator
+ variable / smart parameter
+ vivification
+ # PERL_MAGIC_arylen vtbl_arylen Array length ($#ary)
+ . PERL_MAGIC_pos vtbl_pos pos() lvalue
+ < PERL_MAGIC_backref vtbl_backref back pointer to a weak ref
+ ~ PERL_MAGIC_ext (none) Available for use by extensions
+ : PERL_MAGIC_symtab (none) hash used as symbol table
+ % PERL_MAGIC_rhash (none) hash used as restricted hash
+ @ PERL_MAGIC_arylen_p vtbl_arylen_p pointer to $#a from @a
When an uppercase and lowercase letter both exist in the table, then the
CODE:
hash = newHV();
tie = newRV_noinc((SV*)newHV());
- stash = gv_stashpv("MyTie", TRUE);
+ stash = gv_stashpv("MyTie", GV_ADD);
sv_bless(tie, stash);
hv_magic(hash, (GV*)tie, PERL_MAGIC_tied);
RETVAL = newRV_noinc(hash);
=head2 Scratchpads
The question remains on when the SVs which are I<target>s for opcodes
-are created. The answer is that they are created when the current unit --
-a subroutine or a file (for opcodes for statements outside of
-subroutines) -- is compiled. During this time a special anonymous Perl
-array is created, which is called a scratchpad for the current
-unit.
+are created. The answer is that they are created when the current
+unit--a subroutine or a file (for opcodes for statements outside of
+subroutines)--is compiled. During this time a special anonymous Perl
+array is created, which is called a scratchpad for the current unit.
A scratchpad keeps SVs which are lexicals for the current unit and are
targets for opcodes. One can deduce that an SV lives on a scratchpad
After the compile tree for a subroutine (or for an C<eval> or a file)
is created, an additional pass over the code is performed. This pass
is neither top-down or bottom-up, but in the execution order (with
-additional complications for conditionals). These optimizations are
-done in the subroutine peep(). Optimizations performed at this stage
-are subject to the same restrictions as in the pass 2.
+additional complications for conditionals). Optimizations performed
+at this stage are subject to the same restrictions as in the pass 2.
+
+Peephole optimizations are done by calling the function pointed to
+by the global variable C<PL_peepp>. By default, C<PL_peepp> just
+calls the function pointed to by the global variable C<PL_rpeepp>.
+By default, that performs some basic op fixups and optimisations along
+the execution-order op chain, and recursively calls C<PL_rpeepp> for
+each side chain of ops (resulting from conditionals). Extensions may
+provide additional optimisations or fixups, hooking into either the
+per-subroutine or recursive stage, like this:
+
+ static peep_t prev_peepp;
+ static void my_peep(pTHX_ OP *o)
+ {
+ /* custom per-subroutine optimisation goes here */
+ prev_peepp(o);
+ /* custom per-subroutine optimisation may also go here */
+ }
+ BOOT:
+ prev_peepp = PL_peepp;
+ PL_peepp = my_peep;
+
+ static peep_t prev_rpeepp;
+ static void my_rpeep(pTHX_ OP *o)
+ {
+ OP *orig_o = o;
+ for(; o; o = o->op_next) {
+ /* custom per-op optimisation goes here */
+ }
+ prev_rpeepp(orig_o);
+ }
+ BOOT:
+ prev_rpeepp = PL_rpeepp;
+ PL_rpeepp = my_rpeep;
=head2 Pluggable runops
This function should be as efficient as possible to keep your programs
running as fast as possible.
+=head2 Compile-time scope hooks
+
+As of perl 5.14 it is possible to hook into the compile-time lexical
+scope mechanism using C<Perl_blockhook_register>. This is used like
+this:
+
+ STATIC void my_start_hook(pTHX_ int full);
+ STATIC BHK my_hooks;
+
+ BOOT:
+ BhkENTRY_set(&my_hooks, start, my_start_hook);
+ Perl_blockhook_register(aTHX_ &my_hooks);
+
+This will arrange to have C<my_start_hook> called at the start of
+compiling every lexical scope. The available hooks are:
+
+=over 4
+
+=item C<void start(pTHX_ int full)>
+
+This is called just after starting a new lexical scope. Note that Perl
+code like
+
+ if ($x) { ... }
+
+creates two scopes: the first starts at the C<(> and has C<full == 1>,
+the second starts at the C<{> and has C<full == 0>. Both end at the
+C<}>, so calls to C<start> and C<pre/post_end> will match. Anything
+pushed onto the save stack by this hook will be popped just before the
+scope ends (between the C<pre_> and C<post_end> hooks, in fact).
+
+=item C<void pre_end(pTHX_ OP **o)>
+
+This is called at the end of a lexical scope, just before unwinding the
+stack. I<o> is the root of the optree representing the scope; it is a
+double pointer so you can replace the OP if you need to.
+
+=item C<void post_end(pTHX_ OP **o)>
+
+This is called at the end of a lexical scope, just after unwinding the
+stack. I<o> is as above. Note that it is possible for calls to C<pre_>
+and C<post_end> to nest, if there is something on the save stack that
+calls string eval.
+
+=item C<void eval(pTHX_ OP *const o)>
+
+This is called just before starting to compile an C<eval STRING>, C<do
+FILE>, C<require> or C<use>, after the eval has been set up. I<o> is the
+OP that requested the eval, and will normally be an C<OP_ENTEREVAL>,
+C<OP_DOFILE> or C<OP_REQUIRE>.
+
+=back
+
+Once you have your hook functions, you need a C<BHK> structure to put
+them in. It's best to allocate it statically, since there is no way to
+free it once it's registered. The function pointers should be inserted
+into this structure using the C<BhkENTRY_set> macro, which will also set
+flags indicating which entries are valid. If you do need to allocate
+your C<BHK> dynamically for some reason, be sure to zero it before you
+start.
+
+Once registered, there is no mechanism to switch these hooks off, so if
+that is necessary you will need to do this yourself. An entry in C<%^H>
+is probably the best way, so the effect is lexically scoped; however it
+is also possible to use the C<BhkDISABLE> and C<BhkENABLE> macros to
+temporarily switch entries on and off. You should also be aware that
+generally speaking at least one scope will have opened before your
+extension is loaded, so you will see some C<pre/post_end> pairs that
+didn't have a matching C<start>.
+
=head1 Examining internal data structures with the C<dump> functions
To aid debugging, the source file F<dump.c> contains a number of
state. With multiplicity-enabled perls, PERL_IMPLICIT_CONTEXT is also
normally defined, and enables the support for passing in a "hidden" first
argument that represents all three data structures. MULTIPLICITY makes
-mutli-threaded perls possible (with the ithreads threading model, related
+multi-threaded perls possible (with the ithreads threading model, related
to the macro USE_ITHREADS.)
Two other "encapsulation" macros are the PERL_GLOBAL_STRUCT and
void
Perl_sv_setiv(pTHX_ SV* dsv, IV num)
-C<pTHX_> is one of a number of macros (in perl.h) that hide the
+C<pTHX_> is one of a number of macros (in F<perl.h>) that hide the
details of the interpreter's context. THX stands for "thread", "this",
or "thingy", as the case may be. (And no, George Lucas is not involved. :-)
The first character could be 'p' for a B<p>rototype, 'a' for B<a>rgument,
There are three ways to do this. First, the easy but inefficient way,
which is also the default, in order to maintain source compatibility
-with extensions: whenever XSUB.h is #included, it redefines the aTHX
+with extensions: whenever F<XSUB.h> is #included, it redefines the aTHX
and aTHX_ macros to call a function that will return the context.
Thus, something like:
#include "perl.h"
#include "XSUB.h"
- static my_private_function(int arg1, int arg2);
+ STATIC void my_private_function(int arg1, int arg2);
- static SV *
+ STATIC void
my_private_function(int arg1, int arg2)
{
dTHX; /* fetch context */
#include "XSUB.h"
/* pTHX_ only needed for functions that call Perl API */
- static my_private_function(pTHX_ int arg1, int arg2);
+ STATIC void my_private_function(pTHX_ int arg1, int arg2);
- static SV *
+ STATIC void
my_private_function(pTHX_ int arg1, int arg2)
{
/* dTHX; not needed here, because THX is an argument */
environment) for all the system calls. This makes it possible for
all the system stuff to maintain their own state, broken down into
seven C structures. These are thin wrappers around the usual system
-calls (see win32/perllib.c) for the default perl executable, but for a
+calls (see F<win32/perllib.c>) for the default perl executable, but for a
more ambitious host (like the one that would do fork() emulation) all
the extra work needed to pretend that different interpreters are
actually different "processes", would be done here.
Similarly, all global variables begin with C<PL_>. (By convention,
static functions start with C<S_>.)
-Inside the Perl core, you can get at the functions either with or
-without the C<Perl_> prefix, thanks to a bunch of defines that live in
-F<embed.h>. This header file is generated automatically from
+Inside the Perl core (C<PERL_CORE> defined), you can get at the functions
+either with or without the C<Perl_> prefix, thanks to a bunch of defines
+that live in F<embed.h>. Note that extension code should I<not> set
+C<PERL_CORE>; this exposes the full perl internals, and is likely to cause
+breakage of the XS in each new perl release.
+
+The file F<embed.h> is generated automatically from
F<embed.pl> and F<embed.fnc>. F<embed.pl> also creates the prototyping
header files for the internal functions, generates the documentation
and a lot of other bits and pieces. It's important that when you add
produced a new character set containing all the characters you can
possibly think of and more. There are several ways of representing these
characters, and the one Perl uses is called UTF-8. UTF-8 uses
-a variable number of bytes to represent a character, instead of just
-one. You can learn more about Unicode at http://www.unicode.org/
+a variable number of bytes to represent a character. You can learn more
+about Unicode and Perl's Unicode model in L<perlunicode>.
=head2 How can I recognise a UTF-8 string?
has that byte sequence as well. So you can't tell just by looking - this
is what makes Unicode input an interesting problem.
-The API function C<is_utf8_string> can help; it'll tell you if a string
-contains only valid UTF-8 characters. However, it can't do the work for
-you. On a character-by-character basis, C<is_utf8_char> will tell you
-whether the current character in a string is valid UTF-8.
+In general, you either have to know what you're dealing with, or you
+have to guess. The API function C<is_utf8_string> can help; it'll tell
+you if a string contains only valid UTF-8 characters. However, it can't
+do the work for you. On a character-by-character basis, C<is_utf8_char>
+will tell you whether the current character in a string is valid UTF-8.
=head2 How does UTF-8 represent Unicode characters?
As mentioned above, UTF-8 uses a variable number of bytes to store a
-character. Characters with values 1...128 are stored in one byte, just
-like good ol' ASCII. Character 129 is stored as C<v194.129>; this
+character. Characters with values 0...127 are stored in one byte, just
+like good ol' ASCII. Character 128 is stored as C<v194.128>; this
continues up to character 191, which is C<v194.191>. Now we've run out of
bits (191 is binary C<10111111>) so we move on; 192 is C<v195.128>. And
so it goes on, moving to three bytes at character 2048.
=head2 How does Perl store UTF-8 strings?
Currently, Perl deals with Unicode strings and non-Unicode strings
-slightly differently. If a string has been identified as being UTF-8
-encoded, Perl will set a flag in the SV, C<SVf_UTF8>. You can check and
-manipulate this flag with the following macros:
+slightly differently. A flag in the SV, C<SVf_UTF8>, indicates that the
+string is internally encoded as UTF-8. Without it, the byte value is the
+codepoint number and vice versa (in other words, the string is encoded
+as iso-8859-1, but C<use feature 'unicode_strings'> is needed to get iso-8859-1
+semantics). You can check and manipulate this flag with the
+following macros:
SvUTF8(sv)
SvUTF8_on(sv)
undesirable results.
The problem comes when you have, for instance, a string that isn't
-flagged is UTF-8, and contains a byte sequence that could be UTF-8 -
+flagged as UTF-8, and contains a byte sequence that could be UTF-8 -
especially when combining non-UTF-8 and UTF-8 strings.
Never forget that the C<SVf_UTF8> flag is separate to the PV value; you
The C<char*> string does not tell you the whole story, and you can't
copy or reconstruct an SV just by copying the string value. Check if the
-old SV has the UTF-8 flag set, and act accordingly:
+old SV has the UTF8 flag set, and act accordingly:
p = SvPV(sv, len);
frobnicate(p);
appropriately.
Since just passing an SV to an XS function and copying the data of
-the SV is not enough to copy the UTF-8 flags, even less right is just
+the SV is not enough to copy the UTF8 flags, even less right is just
passing a C<char *> to an XS function.
=head2 How do I convert a string to UTF-8?
-If you're mixing UTF-8 and non-UTF-8 strings, you might find it necessary
-to upgrade one of the strings to UTF-8. If you've got an SV, the easiest
-way to do this is:
+If you're mixing UTF-8 and non-UTF-8 strings, it is necessary to upgrade
+one of the strings to UTF-8. If you've got an SV, the easiest way to do
+this is:
sv_utf8_upgrade(sv);
If you do this in a binary operator, you will actually change one of the
strings that came into the operator, and, while it shouldn't be noticeable
-by the end user, it can cause problems.
+by the end user, it can cause problems in deficient code.
Instead, C<bytes_to_utf8> will give you a UTF-8-encoded B<copy> of its
string argument. This is useful for having the data available for
=item *
Mixing UTF-8 and non-UTF-8 strings is tricky. Use C<bytes_to_utf8> to get
-a new string which is UTF-8 encoded. There are tricks you can use to
-delay deciding whether you need to use a UTF-8 string until you get to a
-high character - C<HALF_UPGRADE> is one of those.
+a new string which is UTF-8 encoded, and then combine them.
=back
need to enter a name and description for your op at the appropriate
place in the C<PL_custom_op_names> and C<PL_custom_op_descs> hashes.
-Forthcoming versions of C<B::Generate> (version 1.0 and above) should
-directly support the creation of custom ops by name.
+C<B::Generate> directly supports the creation of custom ops by name.
=head1 AUTHORS
=head1 SEE ALSO
-perlapi(1), perlintern(1), perlxs(1), perlembed(1)
+L<perlapi>, L<perlintern>, L<perlxs>, L<perlembed>
https://perl5.git.perl.org / perl5.git / blobdiff