bwBASIC/NBS2/P177.BAS

10 PRINT "PROGRAM FILE 177: EXCEPTION - EVALUATION OF NUMERIC"
20 PRINT "        EXPRESSIONS IN THE IF-STATEMENT."
30 PRINT "    ANSI STANDARD 7.5, 10.2"
40 PRINT
50 PRINT "SECTION 177.1: EXCEPTION - EVALUATION OF NUMERIC"
60 PRINT "        EXPRESSIONS IN THE IF-STATEMENT."
70 PRINT
80 PRINT "THIS SECTION TESTS THE EFFECT OF COMPARING EXPRESSIONS"
90 PRINT "WHICH CAUSE NON-FATAL EXCEPTIONS."
100 PRINT
130 PRINT "TO PASS THIS TEST:"
140 PRINT
150 PRINT "    1) TWO EXCEPTIONS MUST BE REPORTED: OVERFLOW, "
160 PRINT "       AND ZERO RAISED TO A NEGATIVE POWER, AND"
170 PRINT
180 PRINT "    2) POSITIVE MACHINE INFINITY MUST BE SUPPLIED AS"
190 PRINT "       THE VALUES OF THE EXPRESSIONS, AND"
200 PRINT
210 PRINT "    3) THE IF MUST TEST EQUAL, AND EXECUTION CONTINUES."
220 PRINT
222 PRINT "                   BEGIN TEST."
225 PRINT
230 PRINT "ABOUT TO EXECUTE:"
240 PRINT "   IF (-1E-33) ^ (-4444) = 0 ^ (-1E-33)"
250 LET A=0
260 LET B=-4444
270 LET C=-1E-33
280 PRINT
290 IF C^B = A^C THEN 320
300 PRINT "*** TEST FAILED: 'IF' TESTED AS UNEQUAL ***"
310 GOTO 350
320 PRINT "IF OVERFLOW AND ZERO TO NEGATIVE POWER EXCEPTIONS"
330 PRINT "   WERE REPORTED, THEN"
340 PRINT "*** TEST PASSED ***"
350 PRINT
360 PRINT "                    END TEST."
370 PRINT
380 PRINT "END PROGRAM 177"
390 END