Spectrum ROM: Routine at 09651

The address of this routine is derived from an offset found in the scanning function table.

This routine deals with string quotes, whether simple like "name" or more complex like "a ""white"" lie" or the seemingly redundant VAL$ """a""".

The address of this routine is derived from an offset found in the scanning function table. This routine deals with string quotes, whether simple like "name" or more complex like "a ""white"" lie" or the seemingly redundant VAL$ """a""".
S_QUOTE	09651	RST 24	Fetch the current character.
	09652	INC HL	Point to the start of the string.
	09653	PUSH HL	Save the start address.
	09654	LD BC,0	Set the length to zero.
	09657	CALL S_QUOTE_S	Call the "matching" subroutine.
	09660	JR NZ,S_Q_PRMS	Jump if zero reset - no more quotes.
S_Q_AGAIN	09662	CALL S_QUOTE_S	Call it again for a third quote.
	09665	JR Z,S_Q_AGAIN	And again for the fifth, seventh etc.
	09667	CALL SYNTAX_Z	If testing syntax, jump to reset bit 6 of FLAGS and to continue scanning.
	09670	JR Z,S_Q_PRMS
	09672	RST 48	Make space in the work space for the string and the terminating quote.
	09673	POP HL	Get the pointer to the start.
	09674	PUSH DE	Save the pointer to the first space.
S_Q_COPY	09675	LD A,(HL)	Get a character from the string.
	09676	INC HL	Point to the next one.
	09677	LD (DE),A	Copy last one to work space.
	09678	INC DE	Point to the next space.
	09679	CP "\""	Is last character a '"'?
	09681	JR NZ,S_Q_COPY	If not, jump to copy next one.
	09683	LD A,(HL)	But if it was, do not copy next one; if next one is a '"', jump to copy the one after it; otherwise, finished with copying.
	09684	INC HL
	09685	CP "\""
	09687	JR Z,S_Q_COPY
S_Q_PRMS	09689	DEC BC	Get true length to BC.
Note that the first quote was not counted into the length; the final quote was, and is discarded now. Inside the string, the first, third, fifth, etc., quotes were counted in but the second, fourth, etc., were not.
	09690	POP DE	Restore start of copied string.
This entry point is used by the routine at S_SCREEN.
S_STRING	09691	LD HL,23611	This is FLAGS; this entry point is used whenever bit 6 is to be reset and a string stacked if executing a line. This is done now.
	09694	RES 6,(HL)
	09696	BIT 7,(HL)
	09698	CALL NZ,STK_STO
	09701	JP S_CONT_2	Jump to continue scanning the line.
Note that in copying the string to the work space, every two pairs of string quotes inside the string ("") have been reduced to one pair of string quotes(").