The BBC and Master Computer Public Domain Library

AF1C STR$

Submitted by Steve Fewell

Description:

Set Y to #&FE (meaning that Hexadecimal output of the value is required).
Get the next non-space character after the STR$-token.
If the next charaxcter is not a '~' (tilde), then set Y to 0 (meaning that decimal output of the numeric
value is required), and decrement &1B (BASIC Text Pointer B offset) so that the non-space character
we obtained will be the first one read by the Get value routine (&AD36).
Store Y to the stack, while we get the value.
Call the Get Value routine (&AD36) to return the value pointed to by the BASIC Test Pointer B.
A single value will be returned. If the value starts with an open bracket ("("), then the expression
within the brackets will be evaluated.
If the type of the returned value (A) is 0 (String), then the value is not numeric, so generate a Type mismatch
error.

Otherwise, retrieve the byte from the stack and store the value in location &15. The ASCNUM routine will
use this value to determine whether the numeric value will be converted to a Hexadecimal String or a Decimal String.
Set Y to the type of the variable returned from the Get value routine (A).

If the 4th byte of @% (&0403) is not zero then the @%-number format settings will be used in the conversion of
the numeric value, so call NUMASC routine (at location &A118) to convert the numeric value to an ASCII
string (located in the SWA), Set A to 0 (meaning that the Current value is a String) and exit.

If the 4th byte of @% (&0403) is zero then the @%-number format settings will not be used in the conversion of
the numeric value, so set &37 to 0 (Output format type = General) and call NUMASC routine (at location &A132)
convert the numeric value to an ASCII string (located in the SWA), Set A to 0 (meaning that the Current
value is a String) and exit.

Disassembly for the STR$ routine