Hi Bart, On Thu, Dec 11, 2008 at 10:21 PM, Bart C. Wise wrote:

If I change the loop to be the following, I still get the same error:

\def\myloop#1{% \tempcnta=\the\startcnt% \loop \advance \tempcnta by 1 \if\tempcnta=#1\else \repeat\fi }

Bart

No, you should define like: \def\myloop#1{% \tempcnta=\the\startcnt% \loop \advance \tempcnta by 1 \if\tempcnta<#1\repeat } No \else before \repeat in this case and no \fi outside the loop. Taking a look at the definition, you could find the following code (something like that, I can't remember clearly): \def\loop#1\repeat{\def\body{#1}\iterate} \def\iterate{something to do with \body} You can see there should not be an extra \else in the \body, and you don't need the \fi to enclose it. I don't know whether I've made my point clear. -- Best Regards Chen ---------------------------------------------------------------- Zhi-chu Chen | Shanghai Synchrotron Radiation Facility No. 2019 | Jialuo Rd. | Jiading | Shanghai | P.R. China tel: 086 21 5955 3405 | zhichu.chen.googlepages.com | www.sinap.ac.cn ----------------------------------------------------------------

Hi Bart, On Thu, Dec 11, 2008 at 11:05 PM, Bart C. Wise wrote:

Chen,

Thanks. That makes sense now. However, when I take your code and run it, it only goes through 1 iteration of the loop and exits. I'm puzzled.

Bart

Really? 'cause when I run the following code =============================== \newcount\startcnt \newcount\tempcnta \def\myloop#1{% \message{enter} \tempcnta=\the\startcnt% \loop \message{loop} \advance \tempcnta by 1 \ifnum\tempcnta<#1 \repeat \message{exit}} \starttext \startcnt=1800 \myloop{2008} \stoptext =============================== I got =============================== systems : begin file test2 at line 14 enter loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop loop exit systems : end file test2 at line 20 ) =============================== which infers it works for me. Anyway, I recommand you take the advanced interface as Hans has suggested. It's easier to use, makes more sense and is more ConTeXt-like. -- Best Regards Chen ---------------------------------------------------------------- Zhi-chu Chen | Shanghai Synchrotron Radiation Facility No. 2019 | Jialuo Rd. | Jiading | Shanghai | P.R. China tel: 086 21 5955 3405 | zhichu.chen.googlepages.com | www.sinap.ac.cn ----------------------------------------------------------------

Am Thu, 11 Dec 2008 07:21:56 -0700 schrieb Bart C. Wise:

If I change the loop to be the following, I still get the same error:

\def\myloop#1{% \tempcnta=\the\startcnt% \loop \advance \tempcnta by 1 \if\tempcnta=#1\else \repeat\fi }

No, the \repeat take the place of the \fi. Also you should always end numbers with a space or a \relax to avoid trouble due to tex trying to expand the following commands in search for more numbers. \newcount\startcnt \newcount\tempcnta \def\myloop#1{% \tempcnta=\the\startcnt\relax% \loop \the\tempcnta, \advance \tempcnta by 1 \ifnum\tempcnta<#1 \repeat } \myloop{10} -- Ulrike Fischer

On Thu, 11 Dec 2008, Aditya Mahajan wrote:

On Thu, 11 Dec 2008, Bart C. Wise wrote:

...

When I run the code below (via minimals), I get the following error, why?

\newcount\startcnt \newcount\tempcnta

\def\myloop#1{% \message{enter} \tempcnta=\the\startcnt% \loop \message{loop} \advance \tempcnta by 1 \ifnum\tempcnta>#1\else \repeat\fi \message{exit} }

\starttext \startcnt=1800 \myloop{2008} \stoptext

Do you know of \dostepwiserecurse{from}{to}{step}{body}. For example,

\starttext \dostepwiserecurse{1800}{2008}{1}{We are at \recurselevel \endgraf} \stoptext

There is also doloop. Documentations from syst-ext.tex %D \macros %D {doloop,exitloop} %D %D Sometimes loops are not determined by counters, but by %D (a combinations of) conditions. We therefore implement a %D straightforward loop, which can only be left when we %D explictly exit it. Nesting is supported. First we present %D a more extensive alternative. %D %D \starttyping %D \doloop %D {Some kind of typesetting punishment \par %D \ifnum\pageno>100 \exitloop \fi} %D \stoptyping %D %D When needed, one can call for \type{\looplevel} and %D \type{\loopdepth}. [...] %D We don't have to declare new counters for \type{\looplevel} %D and \type{\loopdepth} because we can use \type{\recurselevel} %D and \type{\recursedepth}. (although I could not get recurselevel or looplevel to work) [...] %D The loop is executed at least once, so beware of situations %D like: %D %D \starttyping %D \doloop {\exitloop some commands} %D \stoptyping %D %D It's just a matter of putting the text into the \type{\if} %D statement that should be there anyway, like in: %D %D \starttyping %D \doloop {\ifwhatever \exitloop \else some commands\fi} %D \stoptyping %D %D You can also quit a loop immediately, by using \type %D {\exitloopnow} instead. Beware, this is more sensitive %D for conditional errors. So, you can write your example as (changed the stopping condition to add \else, just to illustrate that it works) \newcount\startcnt \newcount\tempcnta \def\myloop#1{% \message{enter} \tempcnta=\the\startcnt% \doloop{ \message{loop \the\tempcnta} \advance \tempcnta by 1 \ifnum\tempcnta<#1 \else \exitloop \fi} \message{exit} } \starttext \startcnt=1800 \myloop{2009} \stoptext Aditya