.MODEL SMALL

	.STACK 100h

	.CODE

	ASSUME es:@code
	ASSUME ds:@code
         
Read	EQU  1

Stx	EQU  '"'
Etx	EQU  '"'

DoToPrev MACRO Call TNext #EM 		;Address list following this begins executing.
					;Parameters will be taken from save location
					; as they were in previous code.

DoToOwn  EQU <Call TDataTOS> 		;Address list following this begins executing.
					;Parameters will be taken from inside the
					; address list (immediate operands).
DoEnd    EQU <DW TDrop>			;Current address list stops.
					;Parent code resumes executing.
					;Parameters set to immediate
Next     EQU <JMP TNext>		;Current machine code stops.
					;Parent code resumes executing.

; Start
;--------------------------------------------------------------------

         MOV AX,CS
         MOV ES,AX
         MOV DS,AX
         MOV SI,offset InBuf
         MOV DI,offset OutBuf


         DoToOwn
MetaL:   DW RunEntry
         DW MetaL
         DW WeaveSp
            DoEnd

Object    DB 0

InBuf     DB '|^|x:.              '
          DB '  |1:.              '
          DB '  |0:.              '
          DB '  |str:|BX^xxxxxx01.'
          DB '       |BP^xxxxxx10.'
          DB '       .            '
          DB '  .                 '
          DB 'BP                  '
          DB 100 dup(0)


; The threader is the heart of the language
;--------------------------------------------------------------------


TDrop:   POP BX
TDataTOS:MOV BP,SP
TNext:   POP BX
         ADD BX,2
         PUSH BX
         JMP [BX-2]


StdEntry:
         DoToPrev     
         DW RunEntry  
         DW RunMatch  
         DW RunSucceed
            DoEnd
         
         
WeaveSp: 
;--------------------------------------------------------------------
         DoToOwn
         DW StdEntry
         DW WeaveMatch
         DB " ",0
         DW RunSp
            DoEnd

RunSp:
         INC SI
         NEXT

         DoToOwn
         DW RunEntry
         DW WeaveMatch
         DW RunMatch
         DB " ",0
         DW RunSucceed
         DW RunSp
            DoEnd





WeaveMatch:
;--------------------------------------------------------------------
         CLD
         CMP  BYTE PTR [SI],Stx
         JNE  WeaveEntry
         INC  SI
         MOV  AX,OFFSET MethodMatch
         STOSW
         JMP  @F
MMatch1: STOSB
     @@: LODSB
         CMP AL,Etx
         JNE  MMatch1
         XOR  AL,AL
         STOSB
         NEXT

Match:
MethodMatch:
         CMP  OBJECT,Read
         JE   ReadMatch

         PUSH DI
         PUSH SI
         MOV  DI,[BP+00]
         CALL RunMATCH
         MOV  [BP+00],DI
         JC   @F
         POP  AX                       ; Succeed
         POP  DI
         NEXT
     @@: POP  SI                       ; Fail
         POP  DI
         POP  AX
         NEXT
         
ReadMatch:
;        BEGIN
;        DW SelfInhertParms
;        DW OutUnderline
;        DW OutString
;        DW OutEndUnderline
;        DW End
            

RunMATCH:
         CLD
         XOR  CX,CX
         DEC  CX
         REPZ CMPSB
         CMP  BYTE PTR [DI-1],0
         JZ   @F
         XOR  AX,AX
         REPNZ SCASB
         STC
         RET
         
     @@: DEC  SI
         CLC
         RET



WeaveEntry:
;--------------------------------------------------------------------
         CMP  BYTE PTR [SI],"|"
         JNE  WeavePeriod
         CMP  BP,SP
         JNZ  @F
         SUB  BP,4
     @@: INC  SI
         MOV  AX,OFFSET RunEntry
         STOSW
         MOV  BX,OFFSET LinkEntry
         POP  AX
         PUSH AX
         PUSH DI
         PUSH BX
         PUSH AX
         ADD  DI,2
         NEXT

LinkEntry:
         DW LEntry1
LEntry1:
         CMP  BP,SP
         JNE  @F        ;if BP,SP insync
         ADD  BP,4      ; keep it that way
     @@: POP  BX
         POP  BX
         MOV  [BX],DI
;        MOV  AX,OFFSET RunSucceed
;        STOSW
         NEXT

Entry:
RunEntry:                    ;Insert a FailTo pointer in the stack.
         CMP  BP,SP
         JNZ  @F
         SUB  BP,2
     @@: POP  BX
         MOV  CX,[BX]
         ADD  BX,2
         PUSH CX
         PUSH BX
         NEXT

RunSucceed:                  ;Remove the FailTo pointer made by RunEntry.
         CMP BP,SP
         JNZ @F
         ADD BP,2
     @@: POP AX
         POP BX
         PUSH AX
         NEXT

         
ReadEntry:
;         Con: LeftMargin Indent to CurPos
;              Disp '|'
;              .
         db ' '

WeavePeriod:
;--------------------------------------------------------------------
         CMP BYTE PTR [SI],'.'
         JNE WeaveDefine
         INC SI
         MOV AX,OFFSET TNext
         STOSW
         NEXT
         
ReadPeriod:
;         Con: LeftMargin Outdent to Prev
;              CrLf
;              Disp '.'
;              .

         DB 0

WeaveDefine:
;--------------------------------------------------------------------
         CMP BYTE PTR [SI],":"
         JNE WeaveROL
         INC SI
         MOV AX,OFFSET RunDefine
         STOSW
         MOV AL,0E8h         ; Call
         STOSB
         MOV AX,OFFSET TNext
         STOSW
         NEXT

Define:
RunDefine:
         POP AX
         STOSW
         NEXT

ReadDefine:
;         Con: Disp ':'
;         .



WeaveROL:
         CMP BYTE PTR [SI],11h
         JNE WeaveSTC
         INC SI
         MOV AX,OFFSET RunROL
         STOSW
         NEXT
RunROL:
         ROL BYTE PTR [DI],1
         NEXT



WeaveSTC:
         CMP BYTE PTR [SI],17h
         JNE WeaveCLC
         INC SI
         MOV AX,OFFSET RunSTC
         STOSW
         NEXT
RunSTC:
         STC
         ROL BYTE PTR [DI],1
         NEXT



WeaveCLC:
         CMP BYTE PTR [SI],12h
         JNE Continue
         INC SI
         MOV AX,OFFSET RunCLC
         STOSW
         NEXT
RunCLC:
         CLC
         ROL BYTE PTR [DI],1
         NEXT


         DB 0Eh DUP(11h)

Continue:

OutBuf   DB 100 DUP(0)

END