How many columns are there in each row in a table?
It will vary, depending on the table!
If I want to write a "row" function in PHP, passing in as parameters each of my columns, I don't know the parameter count. But I can find out using the
fun_num_args function, and I can then get each of them using the
func_get_arg function.
Here's an example:
function row() {
$res = "<tr>";
for ($k=0; $k<func_num_args(); $k++) {
$res .= func_get_arg($k);
}
$res .= "</tr>";
return $res;
}
In Python, you can collect a variable number of arguments using a * in the def of the function / method, such as
  def row(*eachcol):
and indeed you could collect named arguments into a dictionary using **.
In Perl, you can check how many arguments you have using $#_, or using @_ in a scalar content
And in Tcl, a final argument called
args in a proc definition will "sponge up" all remaining parameters, no matter how many of them there are.
  proc ceiling {limit args} {
One slight word of caution - it's often much better to pass an array or a list into a function than a variable number of arguments. But if you do need to pass them individually, then the tips above will point you in the right direction for Perl, PHP, Python and Tcl.
(written 2010-08-20)
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