X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/35f70d169f6bc2a00b0ffca8bfd388516c4af70f..312c0cff71e784e116c0ecac4c33bc94d54f78de:/data/variant.hh?ds=sidebyside diff --git a/data/variant.hh b/data/variant.hh index 684f9e35..da0d2a39 100644 --- a/data/variant.hh +++ b/data/variant.hh @@ -1,6 +1,6 @@ # C++ skeleton for Bison -# Copyright (C) 2002-2012 Free Software Foundation, Inc. +# Copyright (C) 2002-2013 Free Software Foundation, Inc. # This program is free software: you can redistribute it and/or modify # it under the terms of the GNU General Public License as published by @@ -51,13 +51,6 @@ m4_define([_b4_char_sizeof_dummy], dummy[]_b4_char_sizeof_counter]) -# b4_char_sizeof_(SYMBOL-NUM) -# --------------------------- -# A comment describing this symbol. -m4_define([b4_char_sizeof_], -[ // b4_symbol([$1], [tag]) -]) - # b4_char_sizeof(SYMBOL-NUMS) # --------------------------- # To be mapped on the list of type names to produce: @@ -69,7 +62,7 @@ m4_define([b4_char_sizeof_], m4_define([b4_char_sizeof], [b4_symbol_if([$1], [has_type], [ -m4_map([b4_char_sizeof_], [$@])dnl +m4_map([ b4_symbol_tag_comment], [$@])dnl char _b4_char_sizeof_dummy@{sizeof([b4_symbol([$1], [type])])@}; ])]) @@ -101,15 +94,30 @@ m4_define([b4_variant_define], typedef variant self_type; /// Empty construction. - inline variant ()]b4_parse_assert_if([ : built (false) , tname (YY_NULL)])[ {} - /// Instantiate a \a T in here. + /// Construct and fill. + template + variant (const T& t)]b4_parse_assert_if([ + : built (true) + , tname (typeid (T).name ())])[ + { + YYASSERT (sizeof (T) <= S); + new (buffer.raw) T (t); + } + + /// Destruction, allowed only if empty. + ~variant () + {]b4_parse_assert_if([ + YYASSERT (!built); + ])[} + + /// Instantiate an empty \a T in here. template - inline T& + T& build () {]b4_parse_assert_if([ YYASSERT (!built); @@ -122,7 +130,7 @@ m4_define([b4_variant_define], /// Instantiate a \a T in here from \a t. template - inline T& + T& build (const T& t) {]b4_parse_assert_if([ YYASSERT (!built); @@ -133,20 +141,9 @@ m4_define([b4_variant_define], return *new (buffer.raw) T (t); } - /// Construct and fill. - template - inline - variant (const T& t)]b4_parse_assert_if([ - : built (true) - , tname (typeid (T).name ())])[ - { - YYASSERT (sizeof (T) <= S); - new (buffer.raw) T (t); - } - /// Accessor to a built \a T. template - inline T& + T& as () {]b4_parse_assert_if([ YYASSERT (built); @@ -157,7 +154,7 @@ m4_define([b4_variant_define], /// Const accessor to a built \a T (for %printer). template - inline const T& + const T& as () const {]b4_parse_assert_if([ YYASSERT (built); @@ -167,30 +164,47 @@ m4_define([b4_variant_define], } /// Swap the content with \a other, of same type. + /// + /// Both variants must be built beforehand, because swapping the actual + /// data requires reading it (with as()), and this is not possible on + /// unconstructed variants: it would require some dynamic testing, which + /// should not be the variant's responsability. + /// Swapping between built and (possibly) non-built is done with + /// variant::move (). template - inline void + void swap (variant& other) {]b4_parse_assert_if([ + YYASSERT (built); + YYASSERT (other.built); YYASSERT (tname == other.tname);])[ - std::swap (as(), other.as());]b4_parse_assert_if([ - std::swap (built, other.built); - std::swap (tname, other.tname);])[ + std::swap (as(), other.as()); } - /// Assign the content of \a other to this. + /// Move the content of \a other to this. + /// /// Destroys \a other. template - inline void - build (variant& other) - { + void + move (variant& other) + {]b4_parse_assert_if([ + YYASSERT (! built);])[ build(); swap(other); other.destroy(); } + /// Copy the content of \a other to this. + template + void + copy (const variant& other) + { + build (other.as ()); + } + /// Destroy the stored \a T. template - inline void + void destroy () { as ().~T ();]b4_parse_assert_if([ @@ -199,6 +213,10 @@ m4_define([b4_variant_define], } private: + /// Prohibit blind copies. + self_type& operator=(const self_type&); + variant (const self_type&); + /// A buffer large enough to store any of the semantic values. /// Long double is chosen as it has the strongest alignment /// constraints. @@ -207,7 +225,8 @@ m4_define([b4_variant_define], long double align_me; char raw[S]; } buffer;]b4_parse_assert_if([ - /// Whether something is contained. + + /// Whether the content is built. bool built; /// If defined, the name of the stored type. const char* tname;])[ @@ -292,14 +311,15 @@ m4_define([b4_symbol_constructor_define_], b4_parser_class_name::make_[]b4_symbol_([$1], [id]) (dnl b4_join(b4_symbol_if([$1], [has_type], [const b4_symbol([$1], [type])& v]), - b4_locations_if([const location_type& l]))) + b4_locations_if([const location_type& l])))[ { - return symbol_type (b4_join([token::b4_symbol([$1], [id])], - b4_symbol_if([$1], [has_type], [v]), - b4_locations_if([l]))); + symbol_type res (token::]b4_symbol([$1], [id])[]b4_locations_if([, l])[); + ]b4_symbol_if([$1], [has_type], [res.value.build (v);])[ + // ]b4_locations_if([res.location = l;])[ + return res; } -])])]) +]])])]) # b4_symbol_constructor_define