Used by the routine at LINE_RUN.
The routine at LINE_USE continues here.
On entry the HL register pair points to the location after the end of the 'next' line to be handled and the DE register pair to the location before the first character of the line. This applies to lines in the program area and also to a line in the editing area - where the next line will be the same line again whilst there are still statements to be interpreted.
|Set NXTLIN for use once the current line has been completed.
|As usual CH-ADD points to the location before the first character to be considered.
|The statement number is fetched.
|The E register is cleared in case EACH_STMT is used.
|Signal 'no jump' by setting NSPPC to +FF.
|The statement number minus one goes into SUBPPC.
|A first statement can now be considered.
|However for later statements the 'starting address' has to be found.
|Jump forward unless the statement does not exist.
|Call the error handling routine.