1: @node Concepts, Programming in Gauche, Introduction, Top
    2: @chapter Concepts
    3: @c NODE ???ʳ?ǰ
    4: 
    5: @c EN
    6: In this chapter I describe a few Gauche's design concepts
    7: that help you to understand how Gauche works.
    8: @c JP
    9: ??ϤǤϡ?Gaucheư????ʤȤʤ뤤???Ĥ??γ?ǰ?????ޤ???
   10: Gauche???????Τ??????ˤʤ??פ??ޤ???
   11: @c COMMON
   12: 
   13: @menu
   14: * Standard conformance::        
   15: * Multibyte Strings::           
   16: * Multibyte scripts::           
   17: * Case-sensitivity::            
   18: * Integrated Object System::   
   19: * Module system::               
   20: * Compilation::                 
   21: @end menu
   22: 
   23: @node Standard conformance, Multibyte Strings, Concepts, Concepts
   24: @section Standard conformance
   25: @c NODE ɸ???ν?
   26: 
   27: @c EN
   28: Gauche conforms "Revised^5 Report of Algorithmic Language Scheme,"
   29: including optional syntax and procedures, except the following features.
   30: @c JP
   31: Gauche?ϡ??ʲ??˵󤲤?????????ץ???????ʸ??³??????Revised^5 Report of Algorithmic Language Scheme" ?˽????Ƥ??ޤ???
   32: @c COMMON
   33: 
   34: @itemize @bullet
   35: @item
   36: @c EN
   37: By default, Gauche reads symbols in case-sensitive way.
   38: A command-line option is provided to make the reader case-insensitive.
   39: (@xref{Case-sensitivity}, for details).
   40: @c JP
   41: ?ǥե????ǡ?Gauche?ϥ????̾????????????ޤ???
   42: ???ޥ?饤?󥪥ץ????ˤ??ơ??ʸ????????ʤ??⡼?ɤ??????뤳?Ȥ??Ǥ??ޤ?(@ref{Case-sensitivity}??????
   43: @c COMMON
   44: @item
   45: @c EN
   46: Continuations created in a certain situation
   47: (specifically, inside a Scheme code that is called from external
   48: C routine) have limited extent (@xref{Continuation}, for details).
   49: @c JP
   50: ?????ﲼ?Ǻ??줿????ϸ¤??????????ƥ???ޤ?
   51: (????ˤϡ?C?Υ????ɤ??饳?????å??Ȥ??ƸƤФ?Scheme??????????????
   52: ??????????????)???ܤ?????ref{Continuation}?򻲾Ȥ??Ʋ???????
   53: @c COMMON
   54: @item
   55: @c EN
   56: Full numeric tower (integer, rational, real and complex numbers) are supported,
   57: but ratinals are only exact, and complex numbers are always inexact.
   58: The reader can recognize '@code{#}' as insignificant digits.
   59: @c JP
   60: ?????umeric tower(??????ô¡¢¼Â¿????????Ý¡??Ȥ?????????
   61: ͭ?????Τ?????Τߤǡ??ޤ?ʣ??????Τ?????Τߤ??ޤ???
   62: ?꡼??ϡ????˱ƶ????ʤ???'@code{#}'????????????????ޤ???
   63: @c COMMON
   64: @item
   65: @c EN
   66: Procedures @code{rationalize}, @code{transcript-on} and @code{transcript-off}
   67: are not supported.
   68: @c JP
   69: ????@code{rationalize}??@code{transcript-on}???Ú¤?code{transcript-off}
   70: ?ϥ??ݡ??Ȥ??????ޤ???@c COMMON
   71: @end itemize
   72: 
   73: @c EN
   74: (Note: A new Scheme standard R6RS has been ratified on September 2007.
   75: Although we don't have a plan to change Gauche to conform R6RS in near future,
   76: we'll gradually add modules that are compatible to R6RS).
   77: @c JP
   78: (???2007ǯ9??????????cheme?????????RS??????????????
   79: Gauche??S???ˤ?????϶ᤤ????ˤϤ??????󤬡?
   80: R6RS?ȸߴ??ʥ⥸?塼??????ä??Ƥ椯ͽ??Ǥ???)
   81: @c COMMON
   82: 
   83: @c EN
   84: Gauche also supports the following SRFIs (Scheme Request for Implementation).
   85: @c JP
   86: Gauche?Ϥޤ????ʲ???RFI?򥵥ݡ??Ȥ??Ƥ??ޤ???
   87: @c COMMON
   88: 
   89: @table @asis
   90: @c EN
   91: @item SRFI-0, Feature-based conditional expansion construct.
   92: As an autoloaded macro.   @xref{Feature conditional}.
   93: @c JP
   94: @item SRFI-0, ??ǽ?١????ξ????
   95: ?????È¥í¡¼?ɤ????Þ¥??????Æ¥??Ý¡??Ȥ???????@ref{Feature conditional}???È¡?
   96: @c COMMON
   97: 
   98: @c EN
   99: @item SRFI-1, List library.
  100: Supported by the module @code{srfi-1}.  @xref{List library}.
  101: (Some of SRFI-1 procedures are built-in).
  102: @c JP
  103: @item SRFI-1, ?ꥹ?ȥ饤?֥?
  104: ?⥸?塼??ode{srfi-1}?ǥ??ݡ??Ȥ???????@ref{List library}???ȡ?
  105: SRFI-1?μ????Τ???????Ĥ???Ȥ߹??ߤˤʤäƤ??ޤ???
  106: @c COMMON
  107: 
  108: @c EN
  109: @item SRFI-2, AND-LET*: an AND with local bindings, a guarded LET* special form.
  110: Supported natively.  @xref{Binding constructs}.
  111: @c JP
  112: @item SRFI-2, AND-LET*: ?ɽ??????? AND?????????LET* ?????????Ȥ߹??ߤǤ???@ref{Binding constructs}???ȡ?
  113: @c COMMON
  114: 
  115: @c EN
  116: @item SRFI-4, Homogeneous numeric vector datatypes.
  117: The module @code{gauche.uvector} provides a superset of
  118: @code{srfi-4} procedures, including arithmetic operations and
  119: generic interface on the SRFI-4 vectors.  @xref{Uniform vectors}.
  120: @c JP
  121: @item SRFI-4, ???Ê¿?Ù¥?????
  122: ?⥸?塼??ode{gauche.uvector}??
  123: @code{srfi-4}?ξ??ߴ???????????ޤ???
  124: Ʊ?⥸?塼????RFI-4?μ????˲ä???
  125: ???ѱ黻?䥸???ͥ????ʥ??󥿥ե????????????????ޤ???@ref{Uniform vectors}???ȡ?
  126: @c COMMON
  127: 
  128: @c EN
  129: @item SRFI-5, A compatible let form with signatures and rest arguments
  130: Supported by the module @code{srfi-5}.  
  131: @xref{A compatible let form with signatures and rest arguments}.
  132: @c JP
  133: @item SRFI-5, ?????ͥ??rest???ߴ???Τ???t???
  134: ?⥸?塼??ode{srfi-5}?ǥ??ݡ??Ȥ???????
  135: @ref{A compatible let form with signatures and rest arguments}???È¡?
  136: @c COMMON
  137: 
  138: @c EN
  139: @item SRFI-6, Basic String Ports.
  140: SRFI-6 procedures are built-in.  @xref{String ports}.
  141: @c JP
  142: @item SRFI-6, ?????????SRFI-6?μ?????Ȥ߹??ߤˤʤäƤ??ޤ???@ref{String ports}???ȡ?
  143: @c COMMON
  144: 
  145: @c EN
  146: @item SRFI-7, Feature-based program configuration language
  147: Supported as an autoloaded macro.  
  148: @xref{Feature-based program configuration language}.
  149: @c JP
  150: @item SRFI-7, ??ǽ?Ù¡????×¥í¥°???????????È¥í¡¼?ɤ????Þ¥??????Æ¥??Ý¡??Ȥ??????Þ¤???
  151: @ref{Feature-based program configuration language}???È¡?
  152: @c COMMON
  153: 
  154: @c EN
  155: @item SRFI-8, receive: Binding to multiple values.
  156: Syntax @code{receive} is built-in.  @xref{Binding constructs}.
  157: @c JP
  158: @item SRFI-8, receive: ¿?«?
  159: ??ʸ@code{receive}??Ȥ߹??ߤˤʤäƤ??ޤ???@ref{Binding constructs}???ȡ?
  160: @c COMMON
  161: 
  162: @c EN
  163: @item SRFI-9, Defining record types.
  164: Supported by the module @code{srfi-9}.  @xref{Record types}.
  165: @c JP
  166: @item SRFI-9, ?쥳???ɷ????
  167: ?⥸?塼??ode{srfi-9}?ǥ??ݡ??Ȥ???????@ref{Record types}???ȡ?
  168: @c COMMON
  169: 
  170: @c EN
  171: @item SRFI-10, Sharp-comma external form.
  172: Built-in.  @xref{Read-time constructor}.
  173: @c JP
  174: @item SRFI-10, Sharp-comma????ե?????Ȥ߹??ߤǤ???@ref{Read-time constructor}???ȡ?
  175: @c COMMON
  176: 
  177: @c EN
  178: @item SRFI-11, Syntax for receiving multiple values.
  179: Supported by the module @code{srfi-11}.  @xref{Let-values}.
  180: @c JP
  181: @item SRFI-11, ¿????????????ʸ
  182: ?⥸?塼??ode{srfi-11}?ǥ??ݡ??Ȥ???????@ref{Let-values}???ȡ?
  183: @c COMMON
  184: 
  185: @c EN
  186: @item SRFI-13, String library
  187: Supported by the module @code{srfi-13}.  @xref{String library}.
  188: (Some of SRFI-13 procedures are built-in).
  189: @c JP
  190: @item SRFI-13, ʸ?????֥?
  191: ?⥸?塼??ode{srfi-13}?ǥ??ݡ??Ȥ???????@ref{String library}???ȡ?
  192: (SRFI-13?μ????Τ????Ĥ???Ȥ߹??ߤˤʤäƤ??ޤ???)
  193: @c COMMON
  194: 
  195: @c EN
  196: @item SRFI-14, Character-set library
  197: Character-set object and a few SRFI-14 procedures are built-in.
  198: @xref{Character set}.
  199: Complete set of SRFI-14 is supported by the module @code{srfi-14}.
  200: @xref{Character-set library}.
  201: @c JP
  202: @item SRFI-14, ʸ???Υ饤?֥?
  203: ʸ???ȴ????RFI-14??????Ȥ߹??ߤˤʤäƤ??ޤ???
  204: @ref{Character set}???ȡ?SRFI-14?δ???ʥ??ݡ??Ȥϥ⥸?塼??ode{srfi-14}
  205: ??󶡤??????ޤ???@ref{Character-set library}???ȡ?
  206: @c COMMON
  207: 
  208: @c EN
  209: @item SRFI-16, Syntax for procedures of variable arity (case-lambda)
  210: Built-in.  @xref{Making Procedures}.
  211: @c JP
  212: @item SRFI-16, ??????³????ʸ (case-lambda)
  213: ??߹??ߤǤ???@ref{Making Procedures}???ȡ?
  214: @c COMMON
  215: 
  216: @c EN
  217: @item SRFI-17, Generalized set!
  218: Built-in.  @xref{Assignments}.
  219: @c JP
  220: @item SRFI-17, ???????줿 set!
  221: ??߹??ߤǤ???@ref{Assignments}???ȡ?
  222: @c COMMON
  223: 
  224: @c EN
  225: @item SRFI-18, Multithreading support
  226: Some SRFI-18 features are built-in, and the rest is in @code{gauche.threads}
  227: module.  @xref{Threads}.
  228: @c JP
  229: @item SRFI-18, ?ޥ??????ɤΥ??ݡ????????Ĥ???RFI-18?ε?ǽ??Ȥ߹??ߤǤ??ꡢ???Ĥ?API??@code{gauche.threads}?⥸?塼?????????????@ref{Threads}???ȡ?
  230: @c COMMON
  231: 
  232: @c EN
  233: @item SRFI-19, Time Data Types and Procedures.
  234: Time data type is Gauche built-in (@xref{Time}).
  235: Complete set of SRFI-19 is supported by the module @code{srfi-19}.
  236: @xref{Time data types and procedures}.
  237: @c JP
  238: @item SRFI-19, ???֥ǡ????η??ȼ???
  239: ???֤Υǡ???????auche??߹??ߤǤ?(@ref{Time}??????
  240: SRFI-19?δ???ʥ??ݡ??Ȥϥ⥸?塼??ode{srfi-19}??󶡤??????ޤ???
  241: @ref{Time data types and procedures}???È¡?
  242: @c COMMON
  243: 
  244: @c EN
  245: @item SRFI-22, Running Scheme scripts on Unix
  246: Supported.  @xref{Writing Scheme scripts}.
  247: @c JP
  248: @item SRFI-22, UNIX ?? Scheme ???????Ȥμ¹????ݡ??Ȥ??????ޤ???@ref{Writing Scheme scripts}???ȡ?
  249: @c COMMON
  250: 
  251: @c EN
  252: @item SRFI-23, Error reporting mechanism.
  253: Built-in.   @xref{Signalling exceptions}.
  254: @c JP
  255: @item SRFI-23, ???顼??𵡹?
  256: ??߹??ߤǤ???@ref{Signalling exceptions}???ȡ?
  257: @c COMMON
  258: 
  259: @c EN
  260: @item SRFI-25, Multi-dimensional array primitives. 
  261: Supported by the module @code{gauche.array}, which defines
  262: superset of SRFI-25.  @xref{Arrays}.
  263: @c JP
  264: @item SRFI-25, ¿???????Υץ??ƥ????⥸?塼??ode{gauche.array}????SRFI-25?ξ??ߴ????ʤäƤ??ޤ???@ref{Arrays}???ȡ?
  265: @c COMMON
  266: 
  267: @c EN
  268: @item SRFI-26, Notation for specializing parameters without currying.
  269: As an autoloaded macro.  @xref{Making Procedures}.
  270: @c JP
  271: @item SRFI-26, ???꡼??????????ѥ???????ü첽??ˡ
  272: ?????È¥í¡¼?ɤ????Þ¥???????????????Þ¤???@ref{Making Procedures}???È¡?
  273: @c COMMON
  274: 
  275: @c EN
  276: @item SRFI-27, Sources of Random Bits.
  277: Supported by the module @code{srfi-27}.  @xref{Sources of random bits}.
  278: @c JP
  279: @item SRFI-27, ??????åȤΥ?????
  280: ?⥸?塼??ode{srfi-27}?ǥ??ݡ??Ȥ???????@ref{Sources of random bits}???ȡ?
  281: @c COMMON
  282: 
  283: @c EN
  284: @item SRFI-28, Basic format strings.
  285: Gauche's built-in @code{format} procedure is a superset of
  286: SRFI-28 @code{format}.  @xref{Output}.
  287: @c JP
  288: @item SRFI-28, ??ե????ޥå????auche??߹??ߤ?code{format}??SRFI-28?Τ??ξ??ߴ????ʤäƤ??ޤ???@ref{Output}???ȡ?
  289: @c COMMON
  290: 
  291: @c EN
  292: @item SRFI-29, Localization
  293: Supported by the module @code{srfi-29}.
  294: @xref{Localization}.
  295: @c JP
  296: @item SRFI-29, ??è²½
  297: ?⥸?塼??ode{srfi-29}?ǥ??ݡ??Ȥ???????
  298: @ref{Localization}???È¡?
  299: @c COMMON
  300: 
  301: @c EN
  302: @item SRFI-30, Nested multi-line comments.
  303: Supported by the native reader.  @xref{Lexical structure}.
  304: @c JP
  305: @item SRFI-30, ?ͥ??Ȥ???ʣ????????ͥ??ƥ??֤Υ꡼??ǥ??ݡ??Ȥ??????ޤ???@ref{Lexical structure}???ȡ?
  306: @c COMMON
  307: 
  308: @c EN
  309: @item SRFI-31, A special form rec for recursive evaluation
  310: Defined as an autoloaded macro.  @xref{Binding constructs}.
  311: @c JP
  312: @item SRFI-31, ?Ƶ?ɾ??Ѥ?ü???????ec
  313: ?????È¥í¡¼?ɤ????Þ¥???????????????Þ¤???@ref{Binding constructs}???È¡?
  314: @c COMMON
  315: 
  316: @c EN
  317: @item SRFI-34, Exception Handling for Programs
  318: Built-in.  @xref{Exceptions}.
  319: (However, Gauche implements srfi-18's semantics of @code{raise} literally,
  320: which differs slightly from srfi-34's.  This may be changed in future.)
  321: @c JP
  322: @item SRFI-34, ?×¥í¥°????ã³°??
  323: ??߹??ߤǤ???@ref{Exceptions}???ȡ?
  324: (â????Gauche??code{raise}?˴ؤ??Ƥ?rfi-18?Υ??ޥ?????????
  325: ??õ¤·¤Æ¤??Æ¡?????srfi-34?ȼ㴳?ۤʤ??????????rfi-34?˹????뤫?⤷??????
  326: @c COMMON
  327: 
  328: @c EN
  329: @item SRFI-35, Conditions
  330: Built-in.  @xref{Conditions}.
  331: @c JP
  332: @item SRFI-35, ?????????
  333: ??߹??ߤǤ???@ref{Conditions}???ȡ?
  334: @c COMMON
  335: 
  336: @c EN
  337: @item SRFI-36, I/O Conditions
  338: Partly supported.  @xref{Conditions}.
  339: @c JP
  340: @item SRFI-36, I/O ?????????
  341: ?ʬŪ?˥??ݡ??Ȥ??????ޤ?.  @ref{Conditions}???ȡ?
  342: @c COMMON
  343: 
  344: @c EN
  345: @item SRFI-37, args-fold: a program argument processor
  346: Supported by the module @code{srfi-37}.
  347: @xref{A program argument processor}.
  348: @c JP
  349: @item SRFI-37, args-fold: ?×¥í¥°?????
  350: ?⥸?塼??ode{srfi-37}?ǥ??ݡ??Ȥ???????
  351: @ref{A program argument processor}???È¡?
  352: @c COMMON
  353: 
  354: @c EN
  355: @item SRFI-38, External Representation for Data With Shared Structure
  356: Built-in.  See @ref{Reading data} and @ref{Output}.
  357: @c JP
  358: @item SRFI-38, ??ͭ?????ǡ????γ??ɽ??
  359: ??߹??ߤǤ???@ref{Reading data}??ref{Output}???ȡ?
  360: @c COMMON
  361: 
  362: @c EN
  363: @item SRFI-39, Parameter objects
  364: Supported by the module @code{gauche.parameter}.
  365: @xref{Parameters}.
  366: @c JP
  367: @item SRFI-39, ?ѥ????????֥????????⥸?塼??ode{gauche.parameter}?ǥ??ݡ??Ȥ???????
  368: @ref{Parameters}???È¡?
  369: @c COMMON
  370: 
  371: @c EN
  372: @item SRFI-40, A Library of Streams
  373: Supported by the module @code{util.stream}.
  374: @xref{Stream library}.
  375: @c JP
  376: @item SRFI-40, ???ȥ꡼?????֥?
  377: ?⥸?塼??ode{util.stream}?ǥ??ݡ??Ȥ??????ޤ???
  378: @xref{Stream library}.
  379: @c COMMON
  380: 
  381: @c EN
  382: @item SRFI-42, Eager comprehensions
  383: Supported by the module @code{srfi-42}.
  384: @xref{Eager comprehensions}.
  385: @c JP
  386: @item SRFI-42, ?????????ɽ??
  387: ?⥸?塼??ode{srfi-42}?ǥ??ݡ??Ȥ???????
  388: @ref{Eager comprehensions}???È¡?
  389: @c COMMON
  390: 
  391: @c EN
  392: @item SRFI-43, Vector library
  393: Supported by the module @code{srfi-43}.
  394: @xref{Vector library}.
  395: @c JP
  396: @item SRFI-43, ?٥????饤?֥?
  397: ?⥸?塼??ode{srfi-43}?ǥ??ݡ??Ȥ???????
  398: @ref{Vector library}???È¡?
  399: @c COMMON
  400: 
  401: @c EN
  402: @item SRFI-45, Primitives for Expressing Iterative Lazy Algorithms
  403: Built-in.
  404: @xref{Delayed evaluation}.
  405: @c JP
  406: @item SRFI-45, ȿ?Ū Lazy ???르?ꥺ????????ؿ??߹??ߤǤ???
  407: @xref{Delayed evaluation}.
  408: @c COMMON
  409: 
  410: @c EN
  411: @item SRFI-55, require-extension
  412: Supported as an autoloaded macro.
  413: @xref{Requiring extensions}.
  414: @c JP
  415: @item SRFI-55, require?γ??
  416: ?????È¥í¡¼?É¥Þ¥??????Æ¥??Ý¡??Ȥ???????
  417: @ref{Requiring extensions}???È¡?
  418: @c COMMON
  419: 
  420: @c EN
  421: @item SRFI-61, A more general @code{cond} clause
  422: Supported natively.  @xref{Conditionals}.
  423: @c JP
  424: @item SRFI-61, ????Ū??code{cond}?
  425: ????ߤǤ???@ref{Conditionals}???ȡ?
  426: @c COMMON
  427: 
  428: @c EN
  429: @item SRFI-62, S-expression comments
  430: Supported by the native reader.  @xref{Lexical structure}.
  431: @c JP
  432: @item SRFI-62, S?????????ͥ??ƥ??֤Υ꡼??ǥ??ݡ??Ȥ??????ޤ???@ref{Lexical structure}???ȡ?
  433: @c COMMON
  434: 
  435: @c EN
  436: @item SRFI-87, @code{=>} in case clauses
  437: Supported natively.  @xref{Conditionals}.
  438: @c JP
  439: @item SRFI-87, case??Ǥ?code{=>}
  440: ????ߤǤ???@ref{Conditionals}???ȡ?
  441: @c COMMON
  442: 
  443: @end table
  444: 
  445: @node Multibyte Strings, Multibyte scripts, Standard conformance, Concepts
  446: @section Multibyte Strings
  447: @c NODE ?Þ¥??Ð¥??????@c EN
  448: Traditionally, a string is considered as a simple array of bytes.
  449: Programmers tend to imagine a string as a simple
  450: array of characters (though a character may occupy more than one byte).
  451: It's not the case in Gauche.
  452: @c JP
  453: ?????ʸ??ñ?ʤ????Ȥ?????ư????Ƥ??ޤ?????
  454: ???Τ???ʸ??????Ȥ???褦?ˤʤäƤ????ñ??ʸ????Ǥ????ͤ???????Ǥ?????
  455: Gauche?ˤ????Ƥϡ??????ǤϤ???????@c COMMON
  456: 
  457: @c EN
  458: Gauche supports @emph{multibyte string} natively,
  459: which means characters are represented by variable number of bytes
  460: in a string.   Gauche retains semantic compatibility of
  461: Scheme string, so such details can be hidden, but it'll helpful
  462: if you know a few points.
  463: @c JP
  464: Gauche???Ū??emph{?ޥ??Х??????򥵥ݡ??Ȥ??ޤ???
  465: ???ʤ???ʸ??????????Х??ȿ?????Ƥ??ޤ???Scheme????????ƥ??֤Υ??ޥ????????ݤ????????ǡ?
  466: ?ܺ٤òµ¤¤Ë¤??ʤ??Ǥ??í¥°???Ͻñ¤±¤Þ¤?????
  467: ???ˤ????뤤???Ĥ?????äƤ??????ۤ???????Ǥ??礦??
  468: @c COMMON
  469: 
  470: @c EN
  471: A string object keeps a type tag and a pointer to the storage
  472: of the string body.  The storage of the body is managed in a sort of
  473: ``copy-on-write''
  474: way---if you take substring, e.g. using directly by @code{substring}
  475: or using regular expression matcher, or even if you copy a string
  476: by @code{copy-string}, the underlying storage is shared
  477: (the ``anchor'' of the string is different, so the copied string
  478: is not @code{eq?} to the original string).
  479: The actual string is copied only if you destructively modify it.
  480: @c JP
  481: ʸ???֥??????ȤϷ????????????ؤΥݥ??󥿤????ޤ???
  482: ʸ????ϡ?opy-on-write?????ޤ??????ʤ???@code{substring}
  483: ????ɽ????ä?????????????ꡢ???뤤???????????ԡ?????????
  484: ʸ???֥??????Ȥ??Τ???̤ˤĤ????ޤ?????ʸ????϶?ͭ????????
  485: ʸ??????ѹ????????ˤΤߡ?ʸ????????ԡ?????????
  486: @c COMMON
  487: 
  488: @c EN
  489: Consequently the algorithm like pre-allocating a string by
  490: @code{make-string} and filling it with @code{string-set!}
  491: becomes @emph{extremely} inefficient in Gauche.  Don't do it.
  492: (It doesn't work with mulitbyte strings anyway).
  493: Sequential access of string is much more efficient
  494: using @emph{string ports} (@xref{String ports}).
  495: @c JP
  496: ???????äơ?@code{make-string}?Ǥ???????????????餫???ᥢ?í¥±???????Ƥ?????@code{string-set!}?ǽ?????Ô¤??褦?Ê¥??르?ꥺ??
  497: Gauche?Ǥ??˸??????ʤ????????Τ褦?ʥ??르?ꥺ???Ȥ??????????Ǥ??礦??
  498: (???Τ褦?ʥ??르?ꥺ???ޥ??Х??????????????????????
  499: ʸ????????Ԥ?????emph{string ports}????Τ?
  500: ??????ˡ?Ǥ? (@ref{String ports}??????
  501: @c COMMON
  502: 
  503: @c EN
  504: String search primitives such as @code{string-scan} (@xref{String utilities})
  505: and regular expression matcher (@xref{Regular expression})
  506: can return a matched string directly, without
  507: using index access at all.
  508: @c JP
  509: @code{string-scan} (@ref{String utilities}???? ????ɽ??
  510: (@ref{Regular expression}???? ?ʤ???????÷¤¹¤????Æ¥??֤ϡ?
  511: ????å?????????˰?????ʸ??ľ???????Ȥ??Ǥ??ޤ???
  512: @c COMMON
  513: 
  514: @c EN
  515: You can choose @emph{internal} encoding scheme at the time of compiling
  516: Gauche.   At runtime, a procedure @code{gauche-character-encoding}
  517: can be used to query the internal encoding.  Currently, the following
  518: internal encodings are supported.
  519: @c JP
  520: Gauche?Υ???????ˡ?ʸ??mph{?????󥳡??ǥ?????򤹤뤳?Ȥ??Ǥ??ޤ???
  521: ?¹Ի??˼???@code{gauche-character-encoding}?ˤ??Ƥɤ?????󥳡??ǥ????ǥ?????뤵?줿????뤳?Ȥ????????
  522: ???ΤȤ??í¡¢?ʲ??Î¥??󥳡??Ç¥??ó¥°¤????Ý¡??Ȥ??????Þ¤???
  523: @c COMMON
  524: 
  525: @table @code
  526: @item euc-jp
  527: @c EN
  528: EUC-JP encoding of ASCII, JIS X 0201 kana, JIS X 0212 and JIS X 0213:2000
  529: Japanese character set.
  530: @c JP
  531: ASCII??JIS X 0201???ʡ?JIS X 0212?ڤ?IS X 0213:2000ʸ????UC-JP
  532: ???󥳡??ǥ???@c COMMON
  533: @item sjis
  534: @c EN
  535: Shift-JIS encoding of JIS X 0201 kana and JIS X 0213:2000
  536: Japanese character set.  For source-code compatibility, the character
  537: code between 0 and 0x7f is mapped to ASCII.
  538: @c JP
  539: JIS X 0201???ʵڤ?IS X 0213:2000ʸ????hift-JIS???󥳡??ǥ??󥰡?
  540: ???????????ɤθߴ???Τ??ᡢʸ?ú¥³¡¼??????7f??ϰϤ?IS X 0201 roman
  541: ?ǤϤʤ?ASCII?˥ޥåפ???????
  542: @c COMMON
  543: @item utf-8
  544: @c EN
  545: UTF-8 encoding of Unicode.
  546: @c JP
  547: Unicode??TF-8???󥳡??ǥ??󥰡?
  548: @c COMMON
  549: @item none
  550: @c EN
  551: 8-bit fixed-length character encoding, with the code between 0 and 0x7f
  552: matches ASCII.  It's up to the application to interpret the string
  553: with certain character encodings.
  554: @c JP
  555: 8?ӥåȸ????????????Ç¥??ó¥°¡?ʸ?ú¥³¡¼??????7f??ϰϤ?SCII???ߤʤ??Þ¤???ʸ???ɤΥ??󥳡??Ç¥??󥰤Ȥ??Ʋ???뤫?Ï¥??ץꥱ??????????Ǥ???
  556: @c COMMON
  557: @end table
  558: 
  559: @c EN
  560: Conversions from other encoding scheme is provided 
  561: as a special port. @xref{Character code conversion}, for details.
  562: @c JP
  563: ¾??????????ǥ??󥰤?????????̤ʥݡ??Ȥ?äƹԤ??ޤ???
  564: @ref{Character code conversion} ?򻲾Ȥ??Ʋ???????
  565: @c COMMON
  566: 
  567: @c EN
  568: The way to specify the encoding of source programs will be
  569: explained in the next section.
  570: @c JP
  571: ???????×¥í¥°???Î¥??󥳡??Ç¥??ó¥°¤?ꤹ??Ë¡?ˤĤ??Ƥ????ξϤ?????Þ¤???
  572: @c COMMON
  573: 
  574: @node Multibyte scripts, Case-sensitivity, Multibyte Strings, Concepts
  575: @section Multibyte scripts
  576: @c NODE ?Þ¥??Ð¥??È¥???????
  577: @c EN
  578: You can use characters other than @code{us-ascii} not only in
  579: literal strings and characters, but in in commens, symbol names,
  580: literal regular expressions, and so on.
  581: @c JP
  582: ????ʸ??ʸ???ˤ⡢?????ȡ????????
  583: ???????ɽ???ʤ?͡??ʲս???@code{us-ascii}?ʳ??????Ȥ????Ȥ??Ǥ??ޤ???
  584: @c COMMON
  585: 
  586: @c EN
  587: So far, Gauche treats any characters other than @code{us-ascii}
  588: as symbol constituent characters.  Unicode defines more than dozen
  589: "space" characters, though, and they will be treated as whitespace
  590: characters in future.  So it's better to avoid those characters
  591: (except in the strings, regexps and characters) for the time being.
  592: @c JP
  593: ???ޤΤȤ??í¡¢Gauche??code{us-ascii}?ʳ???????Æ¡??????
  594: ??????????Æ°????Þ¤???â????Unicode?Ͻ???Ρֶ??????????Ƥ??ê¡¢????Ϥ?????????í¥°??????Ȥ??Æ°??????????ʤ????礦?????äƸ??ߤΤȤ???????????????(ʸ?????ɽ????ʸ???βս???????Ƥ????Τ?????Ǥ??礦??
  595: @c COMMON
  596: 
  597: @c EN
  598: By default, Gauche assumes a Scheme program is written in
  599: its internal character encoding.   It is fine as far as you're writing
  600: scripts to use your own environment, but it becomes a problem if
  601: somebody else tries to use your script and finds out you're using
  602: different character encoding than his/hers.
  603: @c JP
  604: ?Ç¥Õ¥????Ǥϡ?Gauche??cheme?×¥í¥°????che???ʸ???????Ç¥??ó¥°¤??ñ¤«¤??????ΤȤ??Æ°????Þ¤???????????ʬ?ǽñ¤¤¤????????Ȥ?????Ķ??????????ʤ齽ʬ?Ǥ????????????????Ç¥??ó¥°¤???褦????????뤵?줿?Ķ??Ç¥??????Ȥ?餻??????????Ȥʤ?????
  605: @c COMMON
  606: 
  607: @c EN
  608: So, if Gauche finds a comment something like the following within
  609: the first two lines of the program source, it assumes the rest of
  610: the source code is written in @code{<encoding-name>}, and does
  611: the appropriate character encoding conversion to read the source code:
  612: @c JP
  613: ?????Ç¡?Gauche?Ï¡????Τ褦?Ê¥????Ȥ??×¥í¥°?????????????ɤ?2??ܤޤǤ˸??줿???????????????ɤλĤ??ʬ??@code{<encoding-name>}????ꤵ?????󥳡??Ç¥??󥰤ǽñ¤«¤??????ΤȤ??Æ¡?ɬ??ʤ?
  614: Ŭ??ʥ??󥳡??ǥ???Ѵ?????ޤ???
  615: @c COMMON
  616: @example
  617: ;; coding: <encoding-name>
  618: @end example
  619: 
  620: @c EN
  621: More precisely, a comment in either first or second line that matches
  622: a regular expression @code{#/coding[:=]\s*([\w.-]+)/} is recognized, 
  623: and the first submatch is taken as an encoding name.
  624: If there are multiple matches, only the first one is effective.   
  625: The first two lines must not contain characters other than us-ascii
  626: in order for this mechanism to work.
  627: @c JP
  628: ????Τˤϡ?1??ܤޤ?????ܤΥ????Ȥǡ?
  629: ???ɽ??@code{#/coding[:=]\s*([\w.-]+)/}?˥ޥå?????Τ????ä????ˡ?
  630: ?ǽ??ʬ?ޥå?????󥳡??ǥ?????Ȥ??????????????
  631: ʣ??ޥå?????ä????Ϻǽ?????ͭ????????
  632: ???Υᥫ?˥????????뤿???ϡ??ǽ?2?԰??us-ascii?ʳ??????ޤ????褦?ˤ??Ʋ???????
  633: @c COMMON
  634: 
  635: @c EN
  636: The following example tells Gauche that the script is written
  637: in EUC-JP encoding.   Note that the string "@code{-*-}" around the coding
  638: would be recognized by Emacs to select the buffer's encoding
  639: appropriately.
  640: @c JP
  641: ????м?????ϡ?Gauche?ϥ??????Ȥ?euc-jp?ǽ񤫤??????Τ?ǧ?????ޤ???coding??????Ϥ?@code{-*-}"?ϡ?Emacs??
  642: ?Хåե??Υ??󥳡??ǥ??󥰤?ڤ??ꤹ???˻Ȥ??ޤ???
  643: @c COMMON
  644: 
  645: @example
  646: #!/usr/bin/gosh
  647: ;; -*- coding: euc-jp -*-
  648: 
  649: ... script written in euc-jp ...
  650: @end example
  651: 
  652: @c EN
  653: Internally, the handling of this @emph{magic comment} is done by
  654: a special type of port.  See @ref{Coding-aware ports} for the
  655: details.  See also @ref{Loading Scheme file} for how to disable
  656: this feature.
  657: @c JP
  658: ???Ǥϡ?????ü??????Ȥν????̤ʥݡ??Ȥˤ????Ԥ??Ƥ??ޤ????ܺ٤?ref{Coding-aware ports}?򻲾Ȥ??Ʋ???????
  659: ?ޤ??????ν???????褦?ˤ???ˡ?ˤĤ??Ƥ?@ref{Loading Scheme file}?򻲾Ȥ??Ʋ???????
  660: @c COMMON
  661: 
  662: @node Case-sensitivity, Integrated Object System, Multibyte scripts, Concepts
  663: @section Case-sensitivity
  664: @c NODE ?ʸ?????
  665: 
  666: @c EN
  667: Historically, most Lisp-family languages are case-insensitive
  668: for symbols.  Scheme is no exception and R5RS defines symbols are
  669: read in case-insensitive way.  (Note that symbols are case-sensitive
  670: internally even in R5RS Scheme; case-insensitivity is about readers.)
  671: @c JP
  672: Lisp?Ϥθ???????˥?????ʸ????????Ƥ??ޤ????????
  673: Scheme?⤽????????Ǥ??ꡢR5RS?Ǥ⥷?????߹??ޤ????????????򤷤ʤ???????????ޤ???(â????R5RS??ϰ?????????Ǥ??ʸ????????뤳?ȤˤʤäƤޤ???
  674: ????????Ȥ??Ƥ?????ɤ߹??߻??????????)
  675: @c COMMON
  676: 
  677: @c EN
  678: However, nowadays programming is hardly completed in one language.
  679: When you have to interact with other languages that distinguish uppercase
  680: and lowercase characters, it is desirable that Scheme distinguishes them
  681: as well.
  682: @c JP
  683: ?????????ߤǤϡ??×¥í¥°???ó¥°¤????θ?????뤹?뤳?Ȥ????ˤ???????¾?θ?????󥿥ե?????????ç¡¢Scheme¦?Ǥ?ʸ????????????????Ƥ???????????Ǥ???
  684: @c COMMON
  685: 
  686: @c EN
  687: So Gauche has two modes in reading and writing symbols.
  688: @emph{By default, Gauche reads and writes symbols in case-sensitive manner}.
  689: This behavior doesn't conform R5RS.
  690: @c JP
  691: ??????auche?Ǥϡ????????߹??ߤȽ񤭽Ф????ĤΥ⡼?ɤ?դ??ޤ?????
  692: @emph{?ǥե????Υ⡼?ɤǤϡ?Gauche?Υ꡼??ȥ饤???ϥ?????ʸ????????ޤ?}??
  693: ???Τդ????ϸ?̩?ˤ?5RS?˽????ޤ???@c COMMON
  694: 
  695: @example
  696: ; @r{In case-sensitive mode (default)}
  697: (eq? 'a 'A) @result{} #f  ; #t @r{in R5RS}
  698: (symbol->string 'ABC) @result{} "ABC"
  699: (symbol->string 'abc) @result{} "abc"
  700: (display (string->symbol "ABC")) @result{} @r{writes} ABC
  701: (display (string->symbol "abc")) @result{} @r{writes} abc
  702: @end example
  703: 
  704: @c EN
  705: You can make Gauche case-insensitive by giving @code{-fcase-fold}
  706: command-line option to the @code{gosh} interpreter (@xref{Invoking Gosh}).
  707: In this mode, the reader folds uppercase characters in symbols to lowercase
  708: ones.  If a symbol name contains uppercase characters, it is written
  709: out using |-escape (@xref{Symbols}).
  710: @c JP
  711: @code{gosh}???󥿥ץ꥿?ε?ư????code{-fcase-fold}???ޥ?饤???Ϳ??????Gauche???????????ʤ??⡼?ɤ????ޤ? (@ref{Invoking Gosh}??????
  712: ???Υ⡼?ɤǤϡ??꡼??ϥ??????߹??ߤκݤ????ʸ???????ޤ???
  713: ?ʸ??????륷????ؤ??Ƥϡ?`|' ʸ?????????פ????񤭽Ф?????
  714: (@ref{Symbols}??????
  715: @c COMMON
  716: 
  717: @example
  718: ; @r{In case-insensitive mode (with -fcase-fold option)}
  719: (eq? 'a 'A) @result{} #t
  720: (symbol->string 'ABC) @result{} "abc"
  721: (symbol->string 'abc) @result{} "abc"
  722: (display (string->symbol "ABC")) @result{} @r{writes} |ABC|
  723: (display (string->symbol "abc")) @result{} @r{writes} abc
  724: @end example
  725: 
  726: @c EN
  727: Right now, there's no way to switch these two modes back and forth
  728: inside the interpreter.
  729: @c JP
  730: ???ΤȤ??í¡¢???󥿥ץ꥿??椫????Υ⡼?ɤ?????뤳?ȤϤǤ??Þ¤???@c COMMON
  731: 
  732: 
  733: @node Integrated Object System, Module system, Case-sensitivity, Concepts
  734: @section Integrated Object System
  735: @c NODE ??礵?줿???֥??????ȥ????ƥ?@c EN
  736: Gauche has a STklos-style object system, similar to CLOS.
  737: If you have used some kind of object oriented (OO) languages,
  738: you'll find it easy to understand the basic usage:
  739: @c JP
  740: Gauche??LOS?????????STklos???????????Ö¥??????È¥????Æ¥?????Þ¤???
  741: ???ʤ??????餫?Υ??֥??????Ȼظ?(OO)????Ȥä????Ȥ???????
  742: ????ʻȤ???ϴ???ˤ狼?????礦??
  743: @c COMMON
  744: @example
  745: @c EN
  746: ;; @r{Defines a class point, that has x and y coordinate}
  747: @c JP
  748: ;; @r{x, y??????oint???饹???
  749: @c COMMON
  750: (define-class point ()
  751:   ((x :init-value 0)
  752:    (y :init-value 0))
  753:   )
  754: 
  755: (define-method move ((p point) dx dy)
  756:   (inc! (slot-ref p 'x) dx)
  757:   (inc! (slot-ref p 'y) dy))
  758: 
  759: (define-method write-object ((p point) port)
  760:   (format port "[point ~a ~a]"
  761:           (slot-ref p 'x)
  762:           (slot-ref p 'y)))
  763: @end example
  764: 
  765: @c EN
  766: However, if you are familiar with mainstream OO languages but new to CLOS-style
  767: object system, Gauche's object system may look strange
  768: