====== Rules about number arguments ======
When a function is expecting a <number> argument, the following baseline rules
will apply unless the function documents different behavior:

 * A missing argument causes the function to fail and return the empty string.  The function will not have performed any action. \\
 * Integer arguments are converted using strtoimax(3). \\
 * Float arguments are converted using atof(3). \\
 * Integer return values are generated with ltoa() [which is builtin to the client]. \\
 * Float return values are generated with "%.50g" \\
 * "nan" is usually returned if a floating point operationg resulted in an NaN. \\
 * "DOM" is returned if a floating point operation resulted in an EDOM error \\
 * "RANGE" is returned if a floating point operation resulted in an ERANGE error