Changes

In ConTeXt, the optional argument processing is handled as a two-step process. First, we write the command for the end-user as a wrapper command, which calls {{cmd|dosingleempty}}, {{cmd|dodoubleempty}} , {{cmd|dotripleempty}}, ... (from {{src|syst-aux.mkiv}} or {{src|syssyst-gen.mkii}}) to handle the arguments properly -- including the optional ones -- and then calls a "private" command that contains the internals of the macro. Note that this function call does not explicitly refer to the arguments at all.

To define <ttcode>\mycommand[.#1.][.2.]{.3.}</tt>, i.e., with curly braces around a non-optional third argument, you just define <texcode>\def\mycommand{\dodoubleempty\doMycommand}\def\doMycommand[#1][#2]#3{whatever}</texcode> To define <code>\mycommand[with one optional]{text}</code>argument and one mandatory argument, do the following<texcodecontext source="yes">

There is an optional parameter: {\bf #1}\par%

No optional parameter\par%

This is the mandatory text: {\em #2}%

</texcodecontext>

To define <code>\def\mynewcommand{\dosingleempty\doMyNewCommand}\def\doMyNewCommandmycommand[#1][#2]{% \iffirstargument There is an optional parameter: {\bf #13}\par \else No </code> with two optional parameter\par \fi This is the arguments and one mandatory text: {\em #2}}argument, do

<texcode>\starttextdef\mynewcommand[opt]mycommand{Hello People\dodoubleempty\doMycommand}\blankdef\mynewcommanddoMycommand[#1][#2]#3{Hello Peoplewhatever}\stoptext</contexttexcode>

There is an optional parameter: {\bf #1}\par%

No optional parameter\par%

This is the mandatory text: {\em #2}%

\startalignment[center]%

\stopalignment%

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