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Diffstat (limited to 'doc/context/sources/general/manuals/primitives/primitives.tex')
| -rw-r--r-- | doc/context/sources/general/manuals/primitives/primitives.tex | 78 |
1 files changed, 55 insertions, 23 deletions
diff --git a/doc/context/sources/general/manuals/primitives/primitives.tex b/doc/context/sources/general/manuals/primitives/primitives.tex index 23990f4f7..81b42c5b6 100644 --- a/doc/context/sources/general/manuals/primitives/primitives.tex +++ b/doc/context/sources/general/manuals/primitives/primitives.tex @@ -840,6 +840,39 @@ characters, kind of verbatim. \stopoldprimitive +\startnewprimitive[title={\tex {tokenized}}] + +Just as \type {\expanded} has a counterpart \type {\unexpanded}, it makes sense to give +\type {\detokenize} a companion: + +\startbuffer +\edef\foo{\detokenize{\inframed{foo}}} +\edef\oof{\detokenize{\inframed{oof}}} + +\meaning\foo \crlf +\dontleavehmode\foo + +\edef\foo{\tokenized{\foo\foo}} + +\meaning\foo \crlf +\dontleavehmode\foo + +\dontleavehmode\tokenized{\foo\oof} +\stopbuffer + +\typebuffer {\getbuffer} + +This primitive is similar to: + +\starttyping +\def\tokenized#1{\scantextokens\expandafter{\normalexpanded{#1}}} +\stoptyping + +and should be more efficient, not that it matters much as we don't use it that +much (if at all). + +\stopnewprimitive + \startnewprimitive[title={\tex {expanded}}] This primitive complements the two expansion related primitives mentioned in the @@ -851,9 +884,9 @@ examples: \startbuffer \def\A{!} - \def\B#1{\string#1} \B{\A} \crlf - \def\B#1{\string#1} \normalexpanded{\noexpand\B{\A}} \crlf -\normalprotected\def\B#1{\string#1} \B{\A} \crlf + \def\B#1{\string#1} \B{\A} \crlf + \def\B#1{\string#1} \normalexpanded{\noexpand\B{\A}} \crlf +\protected\def\B#1{\string#1} \B{\A} \crlf \stopbuffer \typebuffer {\getbuffer} @@ -1993,9 +2026,10 @@ A protected macro is one that doesn't get expanded unless it is time to do so. For instance, inside an \type {\edef} it just stays what it is. It often makes sense to pass macros as|-|is to (multi|-|pass) file (for tables of contents). -In \CONTEXT\ we use either \type {\normalprotected} or \type {\unexpanded} -because the later was the command we used to achieve the same results before -\ETEX\ introduced this protection primitive. +In \CONTEXT\ we use either \type {\protected} or \type {\unexpanded} because the +later was the command we used to achieve the same results before \ETEX\ +introduced this protection primitive. Originally the \type {\protected} macro was +also defined but it has been dropped. \stopoldprimitive @@ -2056,20 +2090,18 @@ undecided to what extend \CONTEXT\ will use this feature. Say that you have these definitions: \startbuffer - \def \MyMacroA{alpha} -\normalprotected \def \MyMacroB{beta} - \edef \MyMacroC{\MyMacroA\MyMacroB} -\letprotected \MyMacroA - \edef \MyMacroD{\MyMacroA\MyMacroB} -\meaning \MyMacroC\crlf -\meaning \MyMacroD + \def \MyMacroA{alpha} +\protected \def \MyMacroB{beta} + \edef \MyMacroC{\MyMacroA\MyMacroB} +\letprotected \MyMacroA + \edef \MyMacroD{\MyMacroA\MyMacroB} +\meaning \MyMacroC\crlf +\meaning \MyMacroD \stopbuffer \typebuffer -We use \type {\normalprotected} because when the \ETEX\ \type {\protected} -primitive showed up we already had that name in use. The typeset meaning -in this example is: +The typeset meaning in this example is: {\tttf \getbuffer} @@ -2081,13 +2113,13 @@ The complementary operation of \type {\letprotected} can be used to unprotect a macro, so that it gets expandable. \startbuffer - \def \MyMacroA{alpha} -\normalprotected \def \MyMacroB{beta} - \edef \MyMacroC{\MyMacroA\MyMacroB} -\unletprotected \MyMacroB - \edef \MyMacroD{\MyMacroA\MyMacroB} -\meaning \MyMacroC\crlf -\meaning \MyMacroD + \def \MyMacroA{alpha} +\protected \def \MyMacroB{beta} + \edef \MyMacroC{\MyMacroA\MyMacroB} +\unletprotected \MyMacroB + \edef \MyMacroD{\MyMacroA\MyMacroB} +\meaning \MyMacroC\crlf +\meaning \MyMacroD \stopbuffer \typebuffer |