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@@ -1586,7 +1586,8 @@ Each variable name may be postfixed by an attribute
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@producname{attrib}@producbody{@bnfopt{@bnfter{<} @bnfNter{Name} @bnfter{>}}}
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}
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There are two possible attributes:
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-@id{const}, which declares a @x{constant variable},
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+@id{const}, which declares a @emph{constant} or @emph{read-only} variable,
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+@index{constant variable}
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that is, a variable that cannot be assigned to
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after its initialization;
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and @id{close}, which declares a to-be-closed variable @see{to-be-closed}.
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@@ -9118,7 +9119,7 @@ is a more portable solution.
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@simplesect{
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Here we list the incompatibilities that you may find when moving a program
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-from @N{Lua 5.3} to @N{Lua 5.4}.
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+from @N{Lua 5.4} to @N{Lua 5.5}.
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You can avoid some incompatibilities by compiling Lua with
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appropriate options (see file @id{luaconf.h}).
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@@ -9155,51 +9156,6 @@ change between versions.
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@itemize{
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@item{
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-The coercion of strings to numbers in
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-arithmetic and bitwise operations
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-has been removed from the core language.
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-The string library does a similar job
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-for arithmetic (but not for bitwise) operations
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-using the string metamethods.
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-However, unlike in previous versions,
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-the new implementation preserves the implicit type of the numeral
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-in the string.
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-For instance, the result of @T{"1" + "2"} now is an integer,
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-not a float.
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-}
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-
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-@item{
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-Literal decimal integer constants that overflow are read as floats,
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-instead of wrapping around.
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-You can use hexadecimal notation for such constants if you
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-want the old behavior
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-(reading them as integers with wrap around).
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-}
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-
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-@item{
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-The use of the @idx{__lt} metamethod to emulate @idx{__le}
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-has been removed.
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-When needed, this metamethod must be explicitly defined.
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-}
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-
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-@item{
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-The semantics of the numerical @Rw{for} loop
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-over integers changed in some details.
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-In particular, the control variable never wraps around.
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-}
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-
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-@item{
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-A label for a @Rw{goto} cannot be declared where a label with the same
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-name is visible, even if this other label is declared in an enclosing
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-block.
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-}
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-
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-@item{
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-When finalizing an object,
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-Lua does not ignore @idx{__gc} metamethods that are not functions.
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-Any value will be called, if present.
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-(Non-callable values will generate a warning,
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-like any other error when calling a finalizer.)
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}
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}
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@@ -9210,39 +9166,6 @@ like any other error when calling a finalizer.)
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@itemize{
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@item{
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-The function @Lid{print} does not call @Lid{tostring}
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-to format its arguments;
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-instead, it has this functionality hardwired.
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-You should use @idx{__tostring} to modify how values are printed.
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-}
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-
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-@item{
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-The pseudo-random number generator used by the function @Lid{math.random}
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-now starts with a somewhat random seed.
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-Moreover, it uses a different algorithm.
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-}
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-
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-@item{
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-By default, the decoding functions in the @Lid{utf8} library
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-do not accept surrogates as valid code points.
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-An extra parameter in these functions makes them more permissive.
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-}
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-
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-@item{
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-The options @St{setpause} and @St{setstepmul}
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-of the function @Lid{collectgarbage} are deprecated.
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-You should use the new option @St{incremental} to set them.
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-}
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-
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-@item{
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-The function @Lid{io.lines} now returns four values,
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-instead of just one.
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-That can be a problem when it is used as the sole
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-argument to another function that has optional parameters,
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-such as in @T{load(io.lines(filename, "L"))}.
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-To fix that issue,
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-you can wrap the call into parentheses,
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-to adjust its number of results to one.
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}
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}
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@@ -9254,46 +9177,6 @@ to adjust its number of results to one.
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@itemize{
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@item{
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-Full userdata now has an arbitrary number of associated user values.
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-Therefore, the functions @id{lua_newuserdata},
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-@id{lua_setuservalue}, and @id{lua_getuservalue} were
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-replaced by @Lid{lua_newuserdatauv},
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-@Lid{lua_setiuservalue}, and @Lid{lua_getiuservalue},
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-which have an extra argument.
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-
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-For compatibility, the old names still work as macros assuming
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-one single user value.
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-Note, however, that userdata with zero user values
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-are more efficient memory-wise.
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-}
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-
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-@item{
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-The function @Lid{lua_resume} has an extra parameter.
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-This out parameter returns the number of values on
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-the top of the stack that were yielded or returned by the coroutine.
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-(In previous versions,
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-those values were the entire stack.)
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-}
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-
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-@item{
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-The function @Lid{lua_version} returns the version number,
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-instead of an address of the version number.
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-The Lua core should work correctly with libraries using their
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-own static copies of the same core,
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-so there is no need to check whether they are using the same
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-address space.
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-}
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-
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-@item{
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-The constant @id{LUA_ERRGCMM} was removed.
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-Errors in finalizers are never propagated;
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-instead, they generate a warning.
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-}
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-
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-@item{
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-The options @idx{LUA_GCSETPAUSE} and @idx{LUA_GCSETSTEPMUL}
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-of the function @Lid{lua_gc} are deprecated.
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-You should use the new option @id{LUA_GCINC} to set them.
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}
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}
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Roberto Ierusalimschy