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new pattern item '+'
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manual.tex
49
manual.tex
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@ -1,4 +1,4 @@
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% $Id: manual.tex,v 1.30 1999/04/14 20:47:12 roberto Exp roberto $
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% $Id: manual.tex,v 1.31 1999/05/05 19:21:57 roberto Exp roberto $
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\documentclass[11pt]{article}
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\usepackage{fullpage,bnf}
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@ -41,7 +41,7 @@ Waldemar Celes
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\tecgraf\ --- Computer Science Department --- PUC-Rio
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}
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\date{{\small \tt\$Date: 1999/04/14 20:47:12 $ $}}
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\date{{\small \tt\$Date: 1999/05/05 19:21:57 $ $}}
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\maketitle
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@ -1719,9 +1719,9 @@ equivalent to the Lua code:
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lua_pushnumber(4); /* 3rd argument */
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lua_callfunction(lua_getglobal("f")); /* call Lua function */
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lua_pushobject(lua_getresult(1)); /* push first result of the call */
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lua_setglobal("a"); /* sets global variable 'a' */
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lua_pushobject(lua_getresult(2)); /* push second result of the call */
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lua_setglobal("b"); /* sets global variable 'b' */
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lua_setglobal("a"); /* set global variable 'a' */
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lua_pushobject(lua_getresult(2)); /* push second result of the call */
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lua_setglobal("b"); /* set global variable 'b' */
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\end{verbatim}
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Some special Lua functions have exclusive interfaces.
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@ -2459,27 +2459,27 @@ For instance, when \verb|n| is 1 only the first occurrence of
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Here are some examples:
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\begin{verbatim}
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x = gsub("hello world", "(%w%w*)", "%1 %1")
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x = gsub("hello world", "(%w+)", "%1 %1")
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--> x="hello hello world world"
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x = gsub("hello world", "(%w%w*)", "%1 %1", 1)
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x = gsub("hello world", "(%w+)", "%1 %1", 1)
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--> x="hello hello world"
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x = gsub("hello world from Lua", "(%w%w*)%s*(%w%w*)", "%2 %1")
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x = gsub("hello world from Lua", "(%w+)%s*(%w+)", "%2 %1")
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--> x="world hello Lua from"
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x = gsub("home = $HOME, user = $USER", "$(%w%w*)", getenv)
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x = gsub("home = $HOME, user = $USER", "%$(%w+)", getenv)
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--> x="home = /home/roberto, user = roberto" (for instance)
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x = gsub("4+5 = $return 4+5$", "$(.-)%$", dostring)
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x = gsub("4+5 = $return 4+5$", "%$(.-)%$", dostring)
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--> x="4+5 = 9"
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local t = {name="lua", version="3.1"}
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x = gsub("$name - $version", "$(%w%w*)", function (v) return %t[v] end)
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--> x="lua - 3.1"
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local t = {name="lua", version="3.2"}
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x = gsub("$name - $version", "%$(%w+)", function (v) return %t[v] end)
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--> x="lua - 3.2"
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t = {n=0}
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gsub("first second word", "(%w%w*)", function (w) tinsert(%t, w) end)
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gsub("first second word", "(%w+)", function (w) tinsert(%t, w) end)
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--> t={"first", "second", "word"; n=3}
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\end{verbatim}
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@ -2491,7 +2491,7 @@ a \Def{character class} is used to represent a set of characters.
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The following combinations are allowed in describing a character class:
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\begin{description}
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\item[\emph{x}] (where \emph{x} is any character not in the list
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\verb|()%.[]*-?|)
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\verb|^$()%.[]*+-?|)
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--- represents the character \emph{x} itself.
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\item[\T{.}] --- (a dot) represents all characters.
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\item[\T{\%a}] --- represents all letters.
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@ -2507,6 +2507,8 @@ The following combinations are allowed in describing a character class:
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\item[\T{\%\M{x}}] (where \M{x} is any non alphanumeric character) ---
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represents the character \M{x}.
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This is the standard way to escape the magic characters \verb|()%.[]*-?|.
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It is strongly recommended that any control character (even the non magic),
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when used to represent itself in a pattern, should be preceded by a \verb|%|.
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\item[\T{[char-set]}] ---
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Represents the class which is the union of all
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characters in char-set.
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@ -2533,7 +2535,7 @@ In particular, the class \verb|[a-z]| may not be equivalent to \verb|%l|.
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The second form should be preferred for more portable programs.
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\paragraph{Pattern Item:}
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a \Def{pattern item} may be:
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a \Def{pattern item} may be
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\begin{itemize}
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\item
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a single character class,
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@ -2541,12 +2543,16 @@ which matches any single character in the class;
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\item
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a single character class followed by \verb|*|,
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which matches 0 or more repetitions of characters in the class.
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These repetition items will always match the longest possible sequence.
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These repetition items will always match the longest possible sequence;
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\item
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a single character class followed by \verb|+|,
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which matches 1 or more repetitions of characters in the class.
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These repetition items will always match the longest possible sequence;
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\item
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a single character class followed by \verb|-|,
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which also matches 0 or more repetitions of characters in the class.
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Unlike \verb|*|,
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these repetition items will always match the shortest possible sequence.
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these repetition items will always match the shortest possible sequence;
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\item
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a single character class followed by \verb|?|,
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which matches 0 or 1 occurrence of a character in the class;
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@ -2804,7 +2810,7 @@ it uses a default pattern that reads the next line
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A \Def{read pattern} is a sequence of read pattern items.
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An item may be a single character class
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or a character class followed by \verb|?| or by \verb|*|.
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or a character class followed by \verb|?|, by \verb|*|, or by \verb|+|.
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A single character class reads the next character from the input
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if it belongs to the class, otherwise it fails.
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A character class followed by \verb|?| reads the next character
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@ -2813,6 +2819,9 @@ it never fails.
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A character class followed by \verb|*| reads until a character that
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does not belong to the class, or end of file;
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since it can match a sequence of zero characters, it never fails.
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A character class followed by \verb|+| reads until a character that
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does not belong to the class, or end of file;
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it fails if it cannot read at least one character.
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Note that the behavior of read patterns is slightly different from
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the regular pattern matching behavior,
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where a \verb|*| expands to the maximum length \emph{such that}
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@ -2838,7 +2847,7 @@ It is equivalent to the pattern \verb|".*"|.
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\item[``*w''] returns the next word
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(maximal sequence of non white-space characters),
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skipping spaces if necessary, or \nil\ on end of file.
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It is equivalent to the pattern \verb|"{%s*}%S%S*"|.
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It is equivalent to the pattern \verb|"{%s*}%S+"|.
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\end{description}
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\subsubsection*{\ff \T{write ([filehandle, ] value1, ...)}}\Deffunc{write}
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