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@ -1,4 +1,4 @@ |
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% $Id: manual.tex,v 2.13 1997/09/16 19:01:10 roberto Exp $ |
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% $Id: manual.tex,v 1.1 1998/01/02 18:34:00 roberto Exp roberto $ |
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\documentstyle[fullpage,11pt,bnf]{article} |
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@ -38,7 +38,7 @@ Waldemar Celes |
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\tecgraf\ --- Computer Science Department --- PUC-Rio |
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} |
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\date{\small \verb$Date: 1997/09/16 19:01:10 $} |
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\date{\small \verb$Date: 1998/01/02 18:34:00 $} |
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\maketitle |
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@ -486,7 +486,7 @@ function calls can be executed as statements: |
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\produc{stat}{functioncall} |
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\end{Produc}% |
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In this case, returned values are thrown away. |
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Function calls are explained in Section~\ref{functioncall}. |
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Function calls are explained in \See{functioncall}. |
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\subsubsection{Local Declarations} \label{localvar} |
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\Index{Local variables} may be declared anywhere inside a block. |
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@ -522,11 +522,11 @@ Basic expressions are: |
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\end{Produc}% |
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Numbers (numerical constants) and |
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string literals are explained in Section~\ref{lexical}; |
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variables are explained in Section~\ref{assignment}; |
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upvalues are explained in Section~\ref{upvalue}; |
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function definitions (\M{function}) are explained in Section~\ref{func-def}; |
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function call are explained in Section~\ref{functioncall}. |
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string literals are explained in \See{lexical}; |
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variables are explained in \See{assignment}; |
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upvalues are explained in \See{upvalue}; |
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function definitions (\M{function}) are explained in \See{func-def}; |
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function call are explained in \See{functioncall}. |
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An access to a global variable \verb|x| is equivalent to a |
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call \verb|getglobal('x')|; |
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@ -549,7 +549,7 @@ the binary \verb|+| (addition), |
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\verb|/| (division) and \verb|^| (exponentiation), |
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and unary \verb|-| (negation). |
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If the operands are numbers, or strings that can be converted to |
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numbers, according to the rules given in Section~\ref{coercion}, |
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numbers, according to the rules given in \See{coercion}, |
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then all operations except exponentiation have the usual meaning. |
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Otherwise, an appropriate tag method is called \see{tag-method}. |
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An exponentiation always calls a tag method. |
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@ -571,7 +571,7 @@ Numbers and strings are compared in the usual way. |
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Tables, userdata and functions are compared by reference, |
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that is, two tables are considered equal only if they are the same table. |
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The operator \verb|~=| is exactly the negation of equality (\verb|==|). |
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Note that the conversion rules of Section~\ref{coercion} |
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Note that the conversion rules of \See{coercion} |
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\emph{do not} apply to equality comparisons. |
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Thus, \verb|"0"==0| evaluates to false. |
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@ -602,7 +602,7 @@ the second operand is evaluated only when necessary. |
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Lua offers a string \Index{concatenation} operator, |
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denoted by ``\IndexVerb{..}''. |
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If operands are strings or numbers, then they are converted to |
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strings according to the rules in Section~\ref{coercion}. |
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strings according to the rules in \See{coercion}. |
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Otherwise, the ``concat'' tag method is called \see{tag-method}. |
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\subsubsection{Precedence} |
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@ -1313,7 +1313,7 @@ there is no guarantee that such pointer will be valid after the block ends |
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\verb|lua_getcfunction| converts a \verb|lua_Object| to a C function. |
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This \verb|lua_Object| must have type \emph{CFunction}; |
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otherwise, the function returns 0 (the \verb|NULL| pointer). |
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The type \verb|lua_CFunction| is explained in Section~\ref{LuacallC}. |
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The type \verb|lua_CFunction| is explained in \See{LuacallC}. |
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\verb|lua_getuserdata| converts a \verb|lua_Object| to \verb|void*|. |
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This \verb|lua_Object| must have type \emph{userdata}; |
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@ -1672,7 +1672,7 @@ For some examples, see files \verb|lstrlib.c|, |
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\subsection{References to Lua Objects} |
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As noted in Section~\ref{LuacallC}, \verb|lua_Object|s are volatile. |
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As noted in \See{LuacallC}, \verb|lua_Object|s are volatile. |
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If the C code needs to keep a \verb|lua_Object| |
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outside block boundaries, |
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then it must create a \Def{reference} to the object. |
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@ -1893,7 +1893,7 @@ and prints their values in a reasonable format. |
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This function is not intended for formatted output, |
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but as a quick way to show a value, |
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for instance for error messages or debugging. |
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See Section~\ref{libio} for functions for formatted output. |
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See \See{libio} for functions for formatted output. |
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\subsubsection*{\ff \T{tonumber (e [, base])}}\Deffunc{tonumber} |
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This function receives one argument, |
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@ -2710,27 +2710,30 @@ Here is a list of all these incompatibilities. |
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\subsection*{Incompatibilities with \Index{version 3.0}} |
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\begin{itemize} |
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\item The whole library must be explicitly openen before used. |
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\item To support for multiple contexts, |
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the whole library must be explicitly openen before used. |
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However, all standard libraries check whether Lua is already opened, |
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so any program that opens at least one standard library before using |
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Lua API does not need to be corrected. |
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\item Function \verb|dostring| does not accept an optional second argument, |
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with a temporary error method. |
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Now Function \verb|call| offers this facility. |
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This facility is now provided by function \verb|call|. |
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\item Function \verb|gsub| does not accept an optional fourth argument |
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\item Function \verb|gsub| no longer accepts an optional fourth argument |
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(a callback data, a table). |
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Closures make this feature irrelevant. |
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\item The syntax for function declaration is now more restricted; |
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for instance, the old syntax \verb|function f[exp] (x) ... end| is not |
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accepted in 3.1. |
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Progams should use an explicit assignment instead. |
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Progams should use an explicit assignment instead, like this: |
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\verb|f[exp] = function (x) ... end|. |
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\item Old pre-compiled code is obsolete, and must be re-compiled. |
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\item The option \verb|a=b| in Lua stand-alone does not need extra quotes. |
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Check \See{lua-sa} for details. |
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\end{itemize} |
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