Sun Microsystems SunSoft Pascal 4.0 User Manual page 265

Argument domain exception
DOMAIN
Argument singularity
SING
Overflow range exception
OVERFLOW
Underflow range exception
UNDERFLOW
Total loss of significance
TLOSS
Partial loss of significance
PLOSS
If your matherr() function returns a non-zero result, no exception message is
printed, and errno is not set.
program TestMatherr(output);
#include <math_p.h>
function matherr(var info: exception): integer;
begin
case info.kind of
DOMAIN: begin
{ change sqrt to return sqrt(-arg1), not NaN }
if substr(info.name^, 1, length('sqrt')) = 'sqrt' then begin
info.retval := sqrt(-info.arg1);
matherr := 1; { No exception message will be printed }
end;
end;
otherwise
matherr := 0;
end;
end;
begin
writeln('Error handling function');
writeln('sqrt(-1)= ', sqrt(-1));
end.
Math Libraries
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