rarray_value.pdf

Transcript

1. Array#+ ͱ
   Array#concatͷ
   ϝϞϦͷ࢖͍ํͷҧ͍
   @morihirok
   

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2. ഁյతϝιουͱඇഁյతϝ
   ιου
   • ඇഁյతϝιου͸Ϩγʔόͷঢ়ଶʹӨڹΛٴ΅
   ͢
   • Array#+ ͸ඇഁյతϝιου
   • ഁյతϝιου͸Ϩγʔόͷঢ়ଶʹӨڹΛٴ΅͢
   • Array#concat͸ഁյతϝιου
   

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3. #+ ͱ #concat ͷҧ͍
   ary1 = ['hoge', 'fuga']
   ary2 = ['foo', ‘bar']
   ary3 = ary1 + ary2
   p ary3
   => ["hoge", "fuga", "foo", "bar"]
   p ary1
   => ["hoge", “fuga"]
   ary1.concat(ary2)
   p ary1
   => ["hoge", "fuga", "foo", "bar"]
   

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4. ඇഁյతϝιου͸ϝϞϦޮ཰
   ͕ѱ͍ͷͰ͸ʁ
   ary1 = ['hoge', 'fuga']
   ary2 = ['foo', ‘bar']
   ary3 = ary1 + ary2
   p ary3
   => ["hoge", "fuga", "foo", "bar"]
   p ary1
   => ["hoge", “fuga"]
   ary1.concat(ary2)
   p ary1
   => ["hoge", "fuga", "foo", "bar"]
   ৽ͨͳ഑ྻΛੜ੒͍ͯ͠Δ
   

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5. ͱ͍͏Θ͚Ͱௐࠪ
   ary1 = ['hoge', 'fuga']
   ary2 = ['foo', 'bar']
   ary1.object_id
   => 180
   ary1.map(&:object_id)
   => [200, 220]
   ary2.object_id
   => 240
   ary2.map(&:object_id)
   => [260, 280]
   

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6. Array#concat ͷ৔߹
   p ary1.object_id
   => 180
   p ary1.map(&:object_id)
   => [200, 220]
   p ary2.map(&:object_id)
   => [260, 280]
   ary1.concat(ary2)
   p ary1.object_id
   => 180
   p ary1.map(&:object_id)
   => [200, 220, 260, 280]
   ಉҰͷΦϒδΣΫτΛอ࣋͢Δ
   ഑ྻ͕׬੒
   

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7. Array#+ ͷ৔߹
   p ary1.map(&:object_id)
   => [200, 220]
   p ary2.map(&:object_id)
   => [260, 280]
   ary3 = ary1 + ary2
   ary3.object_id
   => 300
   ary3.map(&:object_id)
   => [200, 220, 260, 280]
   ಉҰͷΦϒδΣΫτΛอ࣋͢Δ
   ഑ྻ͕׬੒
   ৽͍͠ΦϒδΣΫτ͕ੜ੒͞Ε
   ͦΕΛอ࣋͢Δ഑ྻ͕Ͱ͖Δͱ
   ࢥ͍ͬͯͨʜ
   

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8. Arrayʹ͍ͭͯ
   צҧ͍͍ͯ͠Δ͔΋͠Εͳ͍
   

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9. Arrayͷߏ଄ମʹ͍ͭͯௐ΂Δ
   struct RArray {
   struct RBasic basic;
   union {
   struct {
   long len;
   union {
   long capa;
   #if defined(__clang__) /* <- clang++ is sane */ || \
   !defined(__cplusplus) /* <- C99 is sane */ || \
   (__cplusplus > 199711L) /* <- C++11 is sane */
   const
   #endif
   VALUE shared_root;
   } aux;
   const VALUE *ptr;
   } heap;
   const VALUE ary[RARRAY_EMBED_LEN_MAX];
   } as;
   };
   

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10. Arrayͷߏ଄ମʹ͍ͭͯௐ΂Δ
    struct RArray {
    struct RBasic basic;
    union {
    struct {
    long len;
    union {
    long capa;
    #if defined(__clang__) /* <- clang++ is sane */ || \
    !defined(__cplusplus) /* <- C99 is sane */ || \
    (__cplusplus > 199711L) /* <- C++11 is sane */
    const
    #endif
    VALUE shared_root;
    } aux;
    const VALUE *ptr;
    } heap;
    const VALUE ary[RARRAY_EMBED_LEN_MAX];
    } as;
    };
    ϫʔΫΞϥ΢ϯυͷΑ͏ͳͷͰ
    ಡΈਐΊ͍ͯ͘ʹ͋ͨͬͯ
    Ұ୴ແࢹͯ͠ΈΔ
    

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11. Arrayͷߏ଄ମʹ͍ͭͯௐ΂Δ
    struct RArray {
    struct RBasic basic;
    union {
    struct {
    long len;
    union {
    long capa;
    const VALUE shared_root;
    } aux;
    const VALUE *ptr;
    } heap;
    const VALUE ary[RARRAY_EMBED_LEN_MAX];
    } as;
    };
    

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12. Arrayͷߏ଄ମʹ͍ͭͯௐ΂Δ
    struct RArray {
    struct RBasic basic;
    union {
    struct {
    long len;
    union {
    long capa;
    const VALUE shared_root;
    } aux;
    const VALUE *ptr;
    } heap;
    const VALUE ary[RARRAY_EMBED_LEN_MAX];
    } as;
    };
    ࣗ਎ͷܕ΍ॴଐΫϥε΍ϑϥά
    શͯͷΦϒδΣΫτߏ଄ମ͕࣋ͭ
    ࣗ਎ͷ഑ྻͷ਺
    ഑ྻͷશମαΠζ
    ڞ༗ϑϥάͬΆ͍
    

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13. Arrayͷߏ଄ମʹ͍ͭͯௐ΂Δ
    struct RArray {
    struct RBasic basic;
    union {
    struct {
    long len;
    union {
    long capa;
    const VALUE shared_root;
    } aux;
    const VALUE *ptr;
    } heap;
    const VALUE ary[RARRAY_EMBED_LEN_MAX];
    } as;
    };
    ࣮ମϝϞϦ΁ͷϙΠϯλ
    ཁૉ਺͕3"33":@&.#&%@-&.@."9ҎԼͩͱ
    3"SSBZߏ଄ମͷதʹ഑ྻΛ࣋ͭΒ͍͠
    

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14. VALUEͱ͸
    • ߏ଄ମ΁ͷϙΠϯλΛද͢
    • ͭ·ΓRubyͷArrayͷ࣮ମϝϞϦ͸ unsigned
    longͷ഑ྻ
    ruby.h :102
    typedef unsigned long VALUE;
    

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15. Array#+ͷ࣮૷
    VALUE
    rb_ary_plus(VALUE x, VALUE y)
    {
    VALUE z;
    long len, xlen, ylen;
    y = to_ary(y);
    xlen = RARRAY_LEN(x);
    ylen = RARRAY_LEN(y);
    len = xlen + ylen;
    z = rb_ary_new2(len);
    ary_memcpy(z, 0, xlen, RARRAY_CONST_PTR_TRANSIENT(x));
    ary_memcpy(z, xlen, ylen, RARRAY_CONST_PTR_TRANSIENT(y));
    ARY_SET_LEN(z, len);
    return z;
    }
    

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16. Array#+ͷ࣮૷
    VALUE
    rb_ary_plus(VALUE x, VALUE y)
    {
    VALUE z;
    long len, xlen, ylen;
    y = to_ary(y);
    xlen = RARRAY_LEN(x);
    ylen = RARRAY_LEN(y);
    len = xlen + ylen;
    z = rb_ary_new2(len);
    ary_memcpy(z, 0, xlen, RARRAY_CONST_PTR_TRANSIENT(x));
    ary_memcpy(z, xlen, ylen, RARRAY_CONST_PTR_TRANSIENT(y));
    ARY_SET_LEN(z, len);
    return z;
    }
    ৽͍͠3"SSBZߏ଄ମΛ࡞Δ
    7"-6&ΛNFNDQZ͢Δ
    ֤ΦϒδΣΫτߏ଄ମΛίϐʔ͢ΔΘ͚Ͱ͸ͳ͍
    

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17. Array#concatͷ࣮૷
    • RArrayߏ଄ମͷheap.aux.capaΛ֬ೝ
    • concatޙͷαΠζΑΓখ͔ͬͨ͞Βmalloc͠
    ͨΓreallocͨ͠Γͯ͠ϝϞϦΛ֬อ͢Δ໛༷
    • Ξϩέʔτ͞ΕͨϝϞϦʹVALUEΛmemcpy
    

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18. ·ͱΊ
    • ArrayͷඇഁյతϝιουͰੜ੒͞ΕΔͷ͸
    unsigned intͷ഑ྻͳͷͰΊͬͪΌ௕͍Array
    ͱ͔Ͱͳ͚Ε͹ϝϞϦޮ཰͸ؾʹ͠ͳͯ͘Α
    ͦ͞͏
    • Rubyͷ࣮૷ΛͪΐͬͱཧղͰ͖ͯΑ͔ͬͨ
    

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