Heroes of Karn: Routine at B5A4

B5A4: Parser: Count Item References

Used by the routines at ParserValidateDirectObject, Parser_ValidateInputTokens and ParserValidateAnyDirectObject.

Parser: Count Item References.

Output
A	The number of references to items in the user input tokens
E	As A
F	The Z flag is set when there are no items present in the input

ParserCountItemReferences

B5A4

LD HL,$AF2E

Set a pointer to the first word token in HL.

B5A7

LD B,$0A

Set a token count in B of 0A which is the total length of the user input tokens.

B5A9

LD E,$00

Initialise the item counter held in E to 00.

Parser_CountItems_Loop

B5AB

LD A,(HL)

Fetch a user input token.

B5AC

CP $FF

Jump to Parser_CountItems_Process if the terminator character (FF) has been reached.

B5AE

JR Z,Parser_CountItems_Process

B5B0

PUSH HL

Remember the token and the count while the object list is searched.

B5B1

PUSH BC

B5B2

LD HL,($AEE2)

Load the pointer for the character-set pointer into HL.

B5B5

LD BC,($AEF2)

Fetch the count of the number of items in the table from the object count.

B5B9

CPIR

Search to see if the item room ID is in the table.

B5BB

POP BC

Restore BC, HL from the stack.

B5BC

POP HL

B5BD

JR NZ,Parser_CountItems_Skip

Jump to Parser_CountItems_Skip if this token doesn't refer to a game item.

This token does point to a game item, so increase the item counter.

B5BF

INC E

Increment item counter by one.

Parser_CountItems_Skip

B5C0

INC HL

Move to the next token.

B5C1

DJNZ Parser_CountItems_Loop

Decrease the token counter by one and loop back to Parser_CountItems_Loop until all the tokens have been evaluated.

Parser_CountItems_Process

B5C3

XOR A

Leave the number of items named in the command in A. The zero flag is set when none were named.

B5C4

OR E

B5C5

RET

Return.

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