From: Vincent Pit Date: Mon, 17 Sep 2012 11:00:01 +0000 (+0200) Subject: This is 0.20 X-Git-Tag: v0.20^0 X-Git-Url: http://git.vpit.fr/?p=perl%2Fmodules%2FScope-Upper.git;a=commitdiff_plain;h=eb7e09bd1e08678c96ad27e68c0ee401105992aa This is 0.20 --- diff --git a/Changes b/Changes index 6a96951..1b94133 100644 --- a/Changes +++ b/Changes @@ -1,5 +1,23 @@ Revision history for Scope-Upper +0.20 2012-09-17 11:00 UTC + + Add : The new yield(@values, $context) function can be used to return + values to any upper scope, including do or map blocks. + The new leave(@values) function is an alias for + yield(@values, HERE). + + Add : The new context_info($context) function return information + about context $context, similarly to what caller() provides + but for any upper scope. + + Chg : Contexts are now normalized. In previous versions, it was + possible for different contexts to refer to the same scope : + for example, "for (my $i = 0; $i < 10; ++$i) { ... }" was + reachable through two contexts, while "for (@array) { ... }" + only by one. Starting from this version, contexts are + normalized so that they always represent an actual scope. + + Doc : C++ compilers are officially NOT supported. + + Fix : Building with a more recent version of perl 5.17.4. + + Fix : Debugger compatibility with perl 5.17.1 and above. + 0.19 2012-09-01 13:25 UTC + Doc : POD headings have been made linkable. + Fix : Building with perl 5.17.4. diff --git a/META.json b/META.json index 544e4ce..65c01ce 100644 --- a/META.json +++ b/META.json @@ -57,5 +57,5 @@ "url" : "http://git.profvince.com/?p=perl%2Fmodules%2FScope-Upper.git" } }, - "version" : "0.19" + "version" : "0.20" } diff --git a/META.yml b/META.yml index 572d374..468b3c3 100644 --- a/META.yml +++ b/META.yml @@ -32,4 +32,4 @@ resources: homepage: http://search.cpan.org/dist/Scope-Upper/ license: http://dev.perl.org/licenses/ repository: http://git.profvince.com/?p=perl%2Fmodules%2FScope-Upper.git -version: 0.19 +version: 0.20 diff --git a/README b/README index e09bd12..46c4cc0 100644 --- a/README +++ b/README @@ -2,7 +2,7 @@ NAME Scope::Upper - Act on upper scopes. VERSION - Version 0.19 + Version 0.20 SYNOPSIS "reap", "localize", "localize_elem", "localize_delete" and "WORDS" : @@ -148,8 +148,11 @@ DESCRIPTION higher contexts with respectively "localize", "localize_elem" and "localize_delete" ; - * return values immediately to an upper level with "unwind", and know - which context was in use then with "want_at" ; + * return values immediately to an upper level with "unwind", "yield" + and "leave" ; + + * gather information about an upper context with "want_at" and + "context_info" ; * execute a subroutine in the setting of an upper subroutine stack frame with "uplevel" ; @@ -246,7 +249,10 @@ FUNCTIONS will be vivified as soon as the localization occurs and emptied when it ends, although it will still exist in its glob. - "localize_delete $what, $key, $context" + "localize_delete" + localize_delete $what, $key; + localize_delete $what, $key, $context; + Introduces the deletion of a variable or an array/hash element delayed to the time of first return into the upper scope denoted by $context. $what can be: @@ -263,13 +269,15 @@ FUNCTIONS "exists" anymore. $key is ignored. "unwind" - unwind @values; + unwind; unwind @values, $context; - Returns @values *from* the context pointed by $context, i.e. from the - subroutine, eval or format at or just above $context, and immediately - restart the program flow at this point - thus effectively returning to - an upper scope. + Returns @values *from* the subroutine, eval or format context pointed by + or just above $context, and immediately restart the program flow at this + point - thus effectively returning @values to an upper scope. If @values + is empty, then the $context parameter is optional and defaults to the + current context (making the call equivalent to a bare "return;") ; + otherwise it is mandatory. The upper context isn't coerced onto @values, which is hence always evaluated in list context. This means that @@ -282,14 +290,55 @@ FUNCTIONS will set $num to 'z'. You can use "want_at" to handle these cases. + "yield" + yield; + yield @values, $context; + + Returns @values *from* the context pointed by or just above $context, + and immediately restart the program flow at this point. If @values is + empty, then the $context parameter is optional and defaults to the + current context ; otherwise it is mandatory. + + "yield" differs from "unwind" in that it can target *any* upper scope + (besides a "s///e" substitution context) and not necessarily a sub, an + eval or a format. Hence you can use it to return values from a "do" or a + "map" block : + + my $now = do { + local $@; + eval { require Time::HiRes } or yield time() => HERE; + Time::HiRes::time(); + }; + + my @uniq = map { + yield if $seen{$_}++; # returns the empty list from the block + ... + } @things; + + Like for "unwind", the upper context isn't coerced onto @values. You can + use the fifth value returned by "context_info" to handle context + coercion. + + "leave" + leave; + leave @values; + + Immediately returns @values from the current block, whatever it may be + (besides a "s///e" substitution context). "leave" is actually a synonym + for "unwind HERE", while "leave @values" is a synonym for "yield + @values, HERE". + + Like for "yield", you can use the fifth value returned by "context_info" + to handle context coercion. + "want_at" my $want = want_at; my $want = want_at $context; - Like "wantarray", but for the subroutine/eval/format at or just above - $context. + Like "wantarray" in perlfunc, but for the subroutine, eval or format + context located at or just above $context. - The previous example can then be "corrected" : + It can be used to revise the example showed in "unwind" : my $num = sub { my @a = ('a' .. 'z'); @@ -299,13 +348,57 @@ FUNCTIONS will rightfully set $num to 26. - "uplevel $code, @args, $context" + "context_info" + my ($package, $filename, $line, $subroutine, $hasargs, + $wantarray, $evaltext, $is_require, $hints, $bitmask, + $hinthash) = context_info $context; + + Gives information about the context denoted by $context, akin to what + "caller" in perlfunc provides but not limited only to subroutine, eval + and format contexts. When $context is omitted, it defaults to the + current context. + + The values returned are, in order : + + * *(index 0)* : the namespace in use when the context was created ; + + * *(index 1)* : the name of the file at the point where the context + was created ; + + * *(index 2)* : the line number at the point where the context was + created ; + + * *(index 3)* : the name of the subroutine called for this context, or + "undef" if this is not a subroutine context ; + + * *(index 4)* : a boolean indicating whether a new instance of @_ was + set up for this context, or "undef" if this is not a subroutine + context ; + + * *(index 5)* : the context (in the sense of "wantarray" in perlfunc) + in which the context (in our sense) is executed ; + + * *(index 6)* : the contents of the string being compiled for this + context, or "undef" if this is not an eval context ; + + * *(index 7)* : a boolean indicating whether this eval context was + created by "require", or "undef" if this is not an eval context ; + + * *(index 8)* : the value of the lexical hints in use when the context + was created ; + + * *(index 9)* : a bit string representing the warnings in use when the + context was created ; + + * *(index 10)* : a reference to the lexical hints hash in use when the + context was created (only on perl 5.10 or greater). + + "uplevel" my @ret = uplevel { ...; return @ret }; - my @ret = uplevel { my @args = @_; ...; return @ret } @args; - my @ret = uplevel { ... } @args, $context; + my @ret = uplevel { my @args = @_; ...; return @ret } @args, $context; my @ret = &uplevel($callback, @args, $context); - Executes the code reference $code with arguments @args as if it were + Executes the code reference $callback with arguments @args as if it were located at the subroutine stack frame pointed by $context, effectively fooling "caller" and "die" into believing that the call actually happened higher in the stack. The code is executed in the context of the @@ -324,6 +417,9 @@ FUNCTIONS my @inverses = target(1, 2, 4); # @inverses contains (0, 0.5, 0.25) my $count = target(1, 2, 4); # $count is 3 + Note that if @args is empty, then the $context parameter is optional and + defaults to the current context ; otherwise it is mandatory. + Sub::Uplevel also implements a pure-Perl version of "uplevel". Both are identical, with the following caveats : @@ -551,13 +647,15 @@ WORDS # $cxt = SCOPE(4), UP SUB UP SUB = UP SUB EVAL = UP CALLER(2) = TOP ... - Where "unwind", "want_at" and "uplevel" point to depending on the $cxt: + Where "unwind", "yield", "want_at", "context_info" and "uplevel" point + to depending on the $cxt: sub { eval { sub { { - unwind @things => $cxt; # or uplevel { ... } $cxt; + unwind @things => $cxt; # or yield @things => $cxt + # or uplevel { ... } $cxt ... } ... @@ -573,8 +671,9 @@ WORDS EXPORT The functions "reap", "localize", "localize_elem", "localize_delete", - "unwind", "want_at" and "uplevel" are only exported on request, either - individually or by the tags ':funcs' and ':all'. + "unwind", "yield", "leave", "want_at", "context_info" and "uplevel" are + only exported on request, either individually or by the tags ':funcs' + and ':all'. The constant "SU_THREADSAFE" is also only exported on request, individually or by the tags ':consts' and ':all'. @@ -639,7 +738,12 @@ CAVEATS version from Sub::Uplevel. DEPENDENCIES - XSLoader (standard since perl 5.006). + perl 5.6. + + A C compiler. This module may happen to build with a C++ compiler as + well, but don't rely on it, as no guarantee is made in this regard. + + XSLoader (core since perl 5.006). SEE ALSO "local" in perlfunc, "Temporary Values via local()" in perlsub. diff --git a/lib/Scope/Upper.pm b/lib/Scope/Upper.pm index e36cbca..4d44d6c 100644 --- a/lib/Scope/Upper.pm +++ b/lib/Scope/Upper.pm @@ -9,13 +9,13 @@ Scope::Upper - Act on upper scopes. =head1 VERSION -Version 0.19 +Version 0.20 =cut our $VERSION; BEGIN { - $VERSION = '0.19'; + $VERSION = '0.20'; } =head1 SYNOPSIS