Routines
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50375: Parser: Process Item
Used by the routine at GameLoop.
Checks that every object the command names is here. For each word in UserInput_Token_1 that is an object, Parser_CheckObjectIsHere looks for one of its items in the current room or the inventory. If none is there, Parser_CheckObjectIsHere has already said so, and this returns with the carry flag set so that the game loop at GameLoop skips the command.
Set up to loop through all word tokens in the token buffer.
Parser_ProcessItem 50375 LD HL,48486 Set a pointer to the word token buffer (UserInput_Token_1) in HL.
50378 LD B,10 Set a counter in B for 10 tokens (the maximum number of words).
Check if there are any tokens to process. Return immediately if the first token is the terminator (255), meaning the input was empty.
ProcessItem_Loop 50380 LD A,(HL) Return if the current token is 255 (no more tokens to process).
50381 CP 255
50383 RET Z
Check if this token refers to a game item by searching the object list table.
50384 PUSH HL Stash the token pointer and counter on the stack for later restoration.
50385 PUSH BC
50386 LD HL,(48414) Load the object list table pointer into HL.
50389 LD BC,(48426) Load the number of objects into BC (for the CPIR search).
50393 CPIR Search the object list table to see if the token matches any object ID.
50395 JR NZ,ProcessItem_NextToken Jump to ProcessItem_NextToken if the token doesn't match any object ID (not an item token).
The token matches an object ID. Now verify that the item is actually present (in the current room or player's inventory).
50397 CALL Parser_CheckObjectIsHere Call Parser_CheckObjectIsHere to check if the item is present and accessible.
50400 JR NC,ProcessItem_NextToken Jump to ProcessItem_NextToken if the object is here (carry flag clear).
The object isn't here and Parser_CheckObjectIsHere has printed why.
50402 POP BC Restore the token pointer and counter from the stack.
50403 POP HL
50404 RET Return with the carry flag set.
This word isn't an object, or the object is here. Move on to the next word.
ProcessItem_NextToken 50405 POP BC Restore the token pointer and counter from the stack.
50406 POP HL
50407 INC HL Move to the next token in the buffer.
50408 DJNZ ProcessItem_Loop Decrease the counter by one and loop back to ProcessItem_Loop until all 10 tokens have been checked.
50410 RET Return (every object named is here).
View the equivalent code in;
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