Prev: 07406 Up: Map Next: 07427
The address of this routine is found in the parameter table.
On entry the value of the expression between the IF and the THEN is the 'last value' on the calculator stack. If this is logically true then the next statement is considered; otherwise the line is considered to have been finished.
IF_CMD 07408 POP BC Drop the return address - STMT_RET.
07409 CALL SYNTAX_Z Jump forward if checking syntax.
07412 JR Z,IF_1
Now use the calculator to 'delete' the last value on the calculator stack but leave the DE register pair addressing the first byte of the value.
07414 RST 40 Use the calculator.
07415 DEFB 2 delete
07416 DEFB 56 end_calc
07417 EX DE,HL Make HL point to the first byte and call TEST_ZERO.
07421 JP C,LINE_END If the value was 'FALSE' jump to the next line.
IF_1 07424 JP STMT_L_1 But if 'TRUE' jump to the next statement (after the THEN).
Prev: 07406 Up: Map Next: 07427