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第七回闇PHP勉強会

Transcript

1. XPathͰιʔείʔυݕࡧ
   ҋPHPษڧձ (2016/12/11)
   

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2. ࣗݾ঺հ
   ߴࢁԹ @edvakf
   ϐΫγϒגࣜձࣾ ࣥߦ໾һ CTO
   ISUCON6ຊબग़୊͠·ͨ͠
   JavaScript, PHP, Ruby, Go, Scala ͋ͨΓ͕कඋൣғ
   

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3. ྫ͑͹͜͏͍͏έʔε
   ϓϩδΣΫτͷίʔσΟϯάن໿Ͱ

   in_arrayͷୈ3Ҿ਺ʹtrueΛ౉͢͜ͱ͕ඞਢʹͳͬͨ
   ୈ3Ҿ਺͕trueͰͳ͍ՕॴΛ͢΂ͯݕग़͍ͨ͠
   

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4. grep
   git grep in_array | grep -v true
   in_array(1, [1,2]); ←ݕग़Ͱ͖Δ
   in_array(1, [

   1,

   2,

   ], true); ←͜ͷํ๏Ͱ͸ݕग़Ͱ͖ͳ͍
   

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5. खܰʹݕग़Ͱ͖Δ
   πʔϧ͸ແ͍
   

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6. token_get_all
   % php -r 'var_export(token_get_all("in_array(1, [1, 2]);"));'
   array (
   0 =>
   array (
   0 => 379,
   1 => '2 => 1,
   ),
   1 =>
   array (
   0 => 319,
   1 => 'in_array',
   2 => 1,
   ),
   2 => '(',
   3 =>
   array (
   0 => 317,
   1 => '1',
   2 => 1,
   ),
   4 => ',',
   5 =>
   array (
   0 => 382,
   1 => ' ',
   2 => 1,
   ),
   6 => '[',
   7 =>
   array (
   0 => 317,
   1 => '1',
   2 => 1,
   ),
   8 => ',',
   9 =>
   array (
   0 => 382,
   1 => ' ',
   2 => 1,
   ),
   10 =>
   array (
   0 => 317,
   1 => '2',
   2 => 1,
   ),
   11 => ']',
   12 => ')',
   13 => ';',
   )
   

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7. τʔΫϯྻ͔Β
   ݕࡧ͢Δͷ͸ҙ֎ͱ໘౗
   εςʔτϚγϯΛ࡞Δ
   ಛఆͷจ຺ʢεςʔτʣͰ
   ಛఆͷτʔΫϯΛൃݟͨ͠
   Βܯࠂ
   จ຺ͷωετ͕͋ΓಘΔͷ
   Ͱɺ࣮ࡍʹ͸ӈͷྫΑΓԿ
   ഒ΋ෳࡶʹͳΔ
   

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8. ast\Node::__set_state(array(
   'kind' => 133,
   'flags' => 0,
   'lineno' => 1,
   'children' =>
   array (
   0 =>
   ast\Node::__set_state(array(
   'kind' => 515,
   'flags' => 0,
   'lineno' => 1,
   'children' =>
   array (
   'expr' =>
   ast\Node::__set_state(array(
   'kind' => 2048,
   'flags' => 1,
   'lineno' => 1,
   'children' =>
   array (
   'name' => 'in_array',
   ),
   )),
   'args' =>
   ast\Node::__set_state(array(
   'kind' => 128,
   'flags' => 0,
   'lineno' => 1,
   'children' =>
   array (
   0 => 1,
   1 =>
   ast\Node::__set_state(array(
   'kind' => 130,
   'flags' => 0,
   'lineno' => 1,
   'children' =>
   array (
   0 =>
   ast\Node::__set_state(array(
   'kind' => 525,
   'flags' => 0,
   $code = "$ast = ast\parse_code($code, 35);
   var_export($ast);
   php-ast
   

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9. ASTʹର͢Δݕࡧ
   τʔΫϯྻʹର͢Δݕࡧʹ
   ൺ΂Ε͹·ͩ؆୯͕ͩɺ࠶
   ؼͳͲ͕ग़͖ͯͯ໘౗
   ΍ͬͺΓπϦʔʹର͢Δݕ
   ࡧΫΤϦͱ͍͑͹…
   

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10. XPath
    ASTΛXMLʹม׵͢Ε͹XPath͕࢖͑Δʂ
    XPath͸XMLʹ͓͚Δਖ਼نදݱ
    πϦʔʹର͢Δݕࡧͱ͍͑͹XPath
    ࢓༷͕͔ͬ͠Γ͍࣮ͯͯ͠૷΋ଟ͘ɺղઆจॻ΋ଟ͍
    DSLΛ֮͑Δͷ͸ਏ͍ͷͰɺطʹ஌ͬͯΔDSL͕࢖͑Δͷ͕خ͍͠
    ؆୯ͳΫΤϦ͸؆୯ʹॻ͚ɺͪΐͬͱෳࡶͳΫΤϦ΋ॻ͚Δ
    

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11. php-ast-to-xml
    https://github.com/edvakf/php-ast-to-xml
    

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12. php-ast-xpath
    ୈࡾҾ਺ͷ༩͑ΒΕ͍ͯͳ͍in_arrayΛݕࡧ
    $ php-ast-xpath some.php '//AST_CALL[./expr/
    AST_NAME/name/scalar[@value="in_array"] and
    not(./args/AST_ARG_LIST/*[3])]'

    some.php:10

    some.php:12
    

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13. σϞ
    

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14. ·ͱΊ
    ϊʔυ୳ࡧϓϩάϥϜΛॻ͘ͷ͸େม
    php-astͷग़ྗΛػցతʹXMLʹม׵Ͱ͖Δ
    XPathΛ࢖͑͹؆୯ͳΫΤϦͰgrepΑΓਖ਼֬ʹ

    ιʔείʔυΛݕࡧͰ͖Δ
    

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15. ͔͜͜Β͸ໝ૝
    

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16. php-astͰASTʹͯ͠͠·͏ͱɺAST͔Βݩͷιʔε
    ίʔυʹ໭͢͜ͱ͕Ͱ͖ͳ͍
    token_get_allͰऔಘͨ͠τʔΫϯྻͳΒ࿈݁͢Ε͹ݩ
    ͷιʔείʔυʹ໭ͤΔ
    token_get_allͷ৘ใΛอͬͨ··XMLʹม׵Ͱ͖Ε
    ͹ɺXSLTͰπϦʔม׵ͯ͠PHPʹ໭͢ϦϑΝΫλϦϯ
    άπʔϧ͕Ͱ͖ͦ͏
    →LISPͷϚΫϩͩ
    

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