You can find the number of the first character of line x in a HyperCard
field by using the following script:
if x = 1
then
put 1 into charNum
else
put (the length of line 1 to (x-1) of fld test) + 1 into charNum
end if
The only problem with the script is that HyperCard considers a line as a line
only if it is terminated with a carriage return. Line endings that result from
word-wrap in a field are not counted as lines.
For example, a field set to display eight characters wide is filled with 20,000
characters without a carriage return. The display shows approximately x lines,
but HyperCard considers the field to only have one line.
Since HyperCard returns only a null-terminated string of characters as field
contents, you cannot use an XCMD to retrieve the line-starts information.