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https://github.com/diemheych/PrimeFORTH
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Python source for HP Prime FORTH
HP Prime FORTH in Python code including required wrapper to run on HP Prime
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diemheych
GitHub
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451
FORTH.py
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451
FORTH.py
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#PYTHON name
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#
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# forth.py
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#
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import sys, math
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import hpprime
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import graphic
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import urandom
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if sys.version > '3' : raw_input = input # for both 2.7 and 3.0+
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ds = [] # The data stack
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cStack = [] # The control struct stack
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heap = [0]*2048 # The data heap
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heapNext = 0 # Next avail slot in heap
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words = [] # The input stream of tokens
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colour = 0x0000ff
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background = 0xffffff
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initCode = """: cr 10 emit ; : abs dup 0 < if 0 swap - then ; : constant create , does> @ ; : variable create 1 allot ; : +! DUP @ ROT + SWAP ! ;
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: 2DUP OVER OVER ; : 2DROP DROP DROP ; : NIP SWAP DROP ; : 2NIP 2SWAP 2DROP ; : TUCK SWAP OVER ;
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: BL 32 ; : CR 10 EMIT ; : SPACE BL EMIT ; : NEGATE 0 SWAP - ; : DNEGATE 0. 2SWAP D- ; : CELLS CELL * ; : TRUE -1 ; : FALSE 0 ;
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: 0= 0 = ; : 0< 0 < ; : 0> 0 > ; : <= > 0= ; : >= < 0= ; : 0<= 0 <= ; : 0>= 0 >= ; : 1- 1 - ;
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: 2+ 2 + ; : 2- 2 - ; : 2/ 2 / ; : 2* 2 * ; : MIN 2DUP < IF DROP ELSE NIP THEN ; : MAX 2DUP > IF DROP ELSE NIP THEN ; : D0= OR 0= ; 1 constant CELL
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"""
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def main() :
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global words, initCode
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if len(sys.argv) > 1 :
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initCode = open(sys.argv[1]).read() # load start file
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hpprime.eval("PRINT") # clear terminal screen
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print("Prime FORTH 1.0")
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while True :
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pcode = compile() # compile/run from user
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if pcode == None : print(""); return
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execute(pcode)
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#============================== Lexical Parsing
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def getWord (prompt="... ") :
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global words, initCode
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while not words :
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try :
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if initCode : lin = initCode; initCode=""
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else :
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lin = raw_input(prompt)+" "
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print(lin)
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except : return None
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tokenizeWords(lin)
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word = words[0]
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if word == "bye" : return None
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words = words[1:]
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return word
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def tokenizeWords(s) :
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global words # clip comments, split to list of words
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words += s.lower().split() # Use "#" for comment to end of line
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#================================= Runtime operation
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def execute (code) :
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p = 0
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while p < len(code) :
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func = code[p]
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p += 1
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newP = func(code,p)
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if newP != None : p = newP
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def rAdd (cod,p) : b=ds.pop(); a=ds.pop(); ds.append(a+b)
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def rFloor (cod,p) : a=ds.pop(); ds.append(math.floor(a))
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def rMod (cod,p) : b=ds.pop(); a=ds.pop(); ds.append(a%b)
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def rOneplus (cod,p) : a=ds.pop(); ds.append(a+1)
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def rOr (cod,p) : b=ds.pop(); a=ds.pop(); ds.append(a|b)
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def rAnd (cod,p) : b=ds.pop(); a=ds.pop(); ds.append(a&b)
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def rMul (cod,p) : b=ds.pop(); a=ds.pop(); ds.append(a*b)
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def rSub (cod,p) : b=ds.pop(); a=ds.pop(); ds.append(a-b)
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def rDiv (cod,p) : b=ds.pop(); a=ds.pop(); ds.append(a/b)
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def rEq (cod,p) : b=ds.pop(); a=ds.pop(); ds.append(int(a==b))
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def rPixon (cod,p) : y=ds.pop(); x=ds.pop(); hpprime.pixon(0,x,y,colour)
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def rPixon2 (cod,p) :
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y=ds.pop();
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if y > 0 : y = y * 2 + 1
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x=ds.pop()
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if x > 0 : x = x * 2 + 1
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hpprime.pixon(0,x,y,colour);
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hpprime.pixon(0,x+1,y,colour);
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hpprime.pixon(0,x,y+1,colour);
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hpprime.pixon(0,x+1,y+1,colour)
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def rPixon4 (cod,p) :
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y=ds.pop();
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if y > 0 : y = y * 4 + 1
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x=ds.pop()
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if x > 0 : x = x * 4 + 1
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hpprime.fillrect(0,x,y,4, 4, colour, colour);
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def rGetpix (cod,p) : y=ds.pop(); x=ds.pop(); ds.append(hpprime.eval("getpix_p({},{})".format(x,y)))
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def rGetpix2 (cod,p) :
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y=ds.pop();
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if y > 0 : y = y * 2 + 1
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x=ds.pop()
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if x > 0 : x = x * 2 + 1
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ds.append(hpprime.eval("getpix_p({},{})".format(x,y)))
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def rGetpix4 (cod,p) :
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y=ds.pop();
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if y > 0 : y = y * 4 + 1
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x=ds.pop()
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if x > 0 : x = x * 4 + 1
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ds.append(hpprime.eval("getpix_p({},{})".format(x,y)))
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def rLastkey (cod,p) : ds.append(int(hpprime.eval("getkey")))
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def rKey (cod,p) :
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while 1:
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k = hpprime.eval("getkey")
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if k != -1 : break
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ds.append(int(k))
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def rTicks (cod,p) : ds.append(int(hpprime.eval("ticks")))
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def rLine (cod,p) : y2=ds.pop(); x2=ds.pop(); y1=ds.pop(); x1=ds.pop(); hpprime.line(0,x1,y1,x2, y2, colour)
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def rRect (cod,p) : h=ds.pop(); w=ds.pop(); y=ds.pop(); x=ds.pop(); hpprime.rect(0,x,y,w, h, colour)
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def rFillrect (cod,p) : h=ds.pop(); w=ds.pop(); y=ds.pop(); x=ds.pop(); hpprime.fillrect(0,x,y,w, h, colour, colour)
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def rCircle (cod,p) : rad=ds.pop(); y=ds.pop(); x=ds.pop(); hpprime.circle(0,x,y,rad, colour)
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def rCol (cod,p) : global colour ; colour = ds.pop()
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def rGetcol (cod,p) : global colour; ds.append(colour)
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def rBg (cod,p) : global background; background = ds.pop()
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def rShow (cod,p) : graphic.show()
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def rList (cod,p) :
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fname = getWord()+".fth";
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try:
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f = open(fname, "r")
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print(f.read(), end=''); f.close()
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except:
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print(fname+": does not exist")
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def rLoad (cod,p) :
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global initCode
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fname = getWord()+".fth"
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try:
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f = open(fname, "r")
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initCode = f.read()
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f.close()
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except:
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print(fname+": does not exist")
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def rSleep (cod,p) : a=ds.pop()/1000; hpprime.eval("wait({})".format(a))
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def rNeq (cod,p) : b=ds.pop(); a=ds.pop(); ds.append(int(a!=b))
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def rGt (cod,p) : b=ds.pop(); a=ds.pop(); ds.append(int(a>b))
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def rLt (cod,p) : b=ds.pop(); a=ds.pop(); ds.append(int(a<b))
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def rLtE (cod,p) : b=ds.pop(); a=ds.pop(); ds.append(int(a<=b))
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def rSqr (cod,p) : a=ds.pop(); ds.append(math.sqrt(a))
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def rCos (cod,p) : a=ds.pop(); ds.append(math.cos(a))
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def rRandom (cod,p) : a=ds.pop(); ds.append(urandom.randint(0,a-1))
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def rSwap(cod,p) : a=ds.pop(); b=ds.pop(); ds.append(a); ds.append(b)
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def rRot(cod,p) : a=ds.pop(); b=ds.pop(); c=ds.pop(); ds.append(b); ds.append(a); ds.append(c)
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def rDup (cod,p) : ds.append(ds[-1])
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def rDrop(cod,p) : ds.pop()
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def rOver(cod,p) : ds.append(ds[-2])
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def rDump(cod,p) : print("ds = %s" % ds)
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def rDdump(cod,p) : print(rDict)
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def rIdump(cod,p) : print(imDict)
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def rDot (cod,p) : print(ds.pop(),end=' ')
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def rEmit (cod,p) : print(chr(ds.pop()&255),end='')
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def rHere(cod,p) : ds.append(heapNext)
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def rJmp (cod,p) : return cod[p]
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def rJnz (cod,p) : return (cod[p],p+1)[ds.pop()]
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def rJz (cod,p) : return (p+1,cod[p])[ds.pop()==0]
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def rRun (cod,p) :
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if cod[p] in rDict:
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execute(rDict[cod[p]])
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else:
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print(cod[p]," unknown")
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return p+1
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def rPush(cod,p) : ds.append(cod[p]) ; return p+1
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def rCls(cod,p) : graphic.clear_screen(background); hpprime.eval("print")
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def rSin(cod,p) : a=ds.pop(); ds.append(math.sin(a))
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def rCos(cod,p) : a=ds.pop(); ds.append(math.cos(a))
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def rTan(cod,p) : a=ds.pop(); ds.append(math.tan(a))
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def rAsin(cod,p) : a=ds.pop(); ds.append(math.asin(a))
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def rAcos(cod,p) : a=ds.pop(); ds.append(math.acos(a))
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def rAtan(cod,p) : a=ds.pop(); ds.append(math.atan(a))
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def rSqrt(cod,p) : a=ds.pop(); ds.append(math.sqrt(a))
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def rgtR(cod,p) :
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a=ds.pop()
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cStack.append(("NUMBER",a))
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def rRgt(cod,p) :
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name,value=cStack.pop()
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ds.append(value)
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def rRat(cod,p) :
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name,value = cStack.pop()
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cStack.append((name,value))
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ds.append(value)
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def rJ (cod,p) :
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c1,t1 = cStack.pop()
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c2,t2 = cStack.pop()
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c3,t3 = cStack.pop()
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cStack.append((c3,t3))
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cStack.append((c2,t2))
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cStack.append((c1,t1))
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ds.append(t3)
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def rWord (cod,p) :
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word=getWord()
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for c in word :
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ds.append(ord(c))
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ds.append(len(word))
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def rType (cod,p) :
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len = ds.pop()
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addr = ds.pop()
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print("addr ",addr,len)
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for i in range(0, len) :
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print(chr(heap[addr+i]&0x7f),end="")
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def rImmediate(cod,p) :
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imDict[list(rDict.keys())[-1]] = 1
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def rWords(cod,p) :
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for k in sorted(list(rDict.keys())): print(k,end=' ')
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def rCreate (pcode,p) :
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global heapNext, lastCreate
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lastCreate = label = getWord() # match next word (input) to next heap address
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rDict[label] = [rPush, heapNext] # when created word is run, pushes its address
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def rDoes (cod,p) :
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rDict[lastCreate] += cod[p:] # rest of words belong to created words runtime
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return len(cod) # jump p over these
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def rAllot (cod,p) :
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global heapNext
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heapNext += ds.pop() # reserve n words for last create
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def rAt (cod,p) : ds.append(heap[ds.pop()]) # get heap @ address
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def rBang(cod,p) : a=ds.pop(); heap[a] = ds.pop() # set heap @ address
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def rComa(cod,p) : # push tos into heap
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global heapNext
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heap[heapNext]=ds.pop()
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heapNext += 1
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rDict = {
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'+' : rAdd, '-' : rSub, '/' : rDiv, '*' : rMul, 'over': rOver,
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'dup': rDup, 'swap': rSwap, '.': rDot, 'dump' : rDump, 'drop': rDrop,
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'=' : rEq, '>' : rGt, '<': rLt,
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',' : rComa,'@' : rAt, '!' : rBang,'allot': rAllot,
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'create': rCreate, 'does>': rDoes,
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'or' : rOr,
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'and' : rAnd,
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'emit' : rEmit,
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'<>' : rNeq,
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'here' : rHere,
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'rot' : rRot,
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'pixon' : rPixon,
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'pixon2' : rPixon2,
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'pixon4' : rPixon4,
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'getpix' : rGetpix,
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'getpix2' : rGetpix2,
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'getpix4' : rGetpix4,
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'key' : rKey,
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'lastkey' : rLastkey,
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'ticks' : rTicks,
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'line' : rLine,
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'rect' : rRect,
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'fillrect' : rFillrect,
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'circle' : rCircle,
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'sleep' : rSleep,
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'cls' : rCls,
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'col' : rCol,
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'getcol' : rGetcol,
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'bg' : rBg,
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'show' : rShow,
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'list' : rList,
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'load' : rLoad,
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'<>' : rNeq,
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'here' : rHere,
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'rot' : rRot,
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'sin' : rSin,
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'cos' : rCos,
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'random' : rRandom,
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'tan' : rTan,
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'asin' : rAsin,
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'acos' : rAcos,
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'atan' : rAtan,
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'sqrt' : rSqrt,
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'words' : rWords,
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'R@' : rRat,
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'1+' : rOneplus,
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'>r' : rgtR,
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'r>' : rRgt,
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'j' : rJ,
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'type' : rType,
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'word' : rWord,
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'ddump' : rDdump,
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'idump' : rIdump,
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'immediate' : rImmediate,
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'lte' : rLtE,
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}
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#================================= Compile time
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def compile() :
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global ds
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pcode = []; prompt = "Ok " if len(ds)==0 else "Ok: "
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while 1 :
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word = getWord(prompt) # get next word
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if word == None : return None
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cAct = cDict.get(word) # Is there a compile time action ?
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rAct = rDict.get(word) # Is there a runtime action ?
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if cAct : cAct(pcode) # run at compile time
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elif rAct :
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if type(rAct) == type([]) :
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pcode.append(rRun) # Compiled word.
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pcode.append(word) # for now do dynamic lookup
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else : pcode.append(rAct) # push builtin for runtime
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else :
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# Number to be pushed onto ds at runtime
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pcode.append(rPush)
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||||||
|
try : pcode.append(int(word))
|
||||||
|
except :
|
||||||
|
try: pcode.append(float(word))
|
||||||
|
except :
|
||||||
|
pcode[-1] = rRun # Change rPush to rRun
|
||||||
|
pcode.append(word) # Assume word will be defined
|
||||||
|
if not cStack : return pcode
|
||||||
|
prompt = "... "
|
||||||
|
|
||||||
|
def fatal (mesg) : raise mesg
|
||||||
|
|
||||||
|
def cColon (pcode) :
|
||||||
|
if cStack : fatal(": inside Control stack: %s" % cStack)
|
||||||
|
label = getWord()
|
||||||
|
cStack.append(("COLON",label)) # flag for following ";"
|
||||||
|
|
||||||
|
def cSemi (pcode) :
|
||||||
|
if not cStack : fatal("No : for ; to match")
|
||||||
|
code,label = cStack.pop()
|
||||||
|
if code != "COLON" : fatal(": not balanced with ;")
|
||||||
|
rDict[label] = pcode[:] # Save word definition in rDict
|
||||||
|
while pcode : pcode.pop()
|
||||||
|
|
||||||
|
def cBegin (pcode) :
|
||||||
|
cStack.append(("BEGIN",len(pcode))) # flag for following UNTIL
|
||||||
|
|
||||||
|
def cUntil (pcode) :
|
||||||
|
if not cStack : fatal("No BEGIN for UNTIL to match")
|
||||||
|
code,slot = cStack.pop()
|
||||||
|
if code != "BEGIN" : fatal("UNTIL preceded by %s (not BEGIN)" % code)
|
||||||
|
pcode.append(rJz)
|
||||||
|
pcode.append(slot)
|
||||||
|
|
||||||
|
def cWhile (pcode) :
|
||||||
|
if not cStack : fatal("No BEGIN for WHILE to match")
|
||||||
|
pcode.append(rJz)
|
||||||
|
|
||||||
|
def cRepeat (pcode) :
|
||||||
|
if not cStack : fatal("No BEGIN for REPEAT to match")
|
||||||
|
|
||||||
|
def cDo (pcode) :
|
||||||
|
cStack.append(("DO",len(pcode))) # flag for following UNTIL
|
||||||
|
pcode.append(rSwap)
|
||||||
|
pcode.append(rgtR)
|
||||||
|
pcode.append(rgtR)
|
||||||
|
|
||||||
|
def cLoop (pcode) :
|
||||||
|
if not cStack : fatal("No DO for LOOP to match")
|
||||||
|
code,slot = cStack.pop()
|
||||||
|
if code != "DO" : fatal("LOOP preceded by %s (not DO)" % code)
|
||||||
|
pcode.append(rRgt)
|
||||||
|
pcode.append(rRgt)
|
||||||
|
pcode.append(rSwap)
|
||||||
|
pcode.append(rOneplus)
|
||||||
|
pcode.append(rOver)
|
||||||
|
pcode.append(rOver)
|
||||||
|
pcode.append(rEq)
|
||||||
|
pcode.append(rJz)
|
||||||
|
pcode.append(slot)
|
||||||
|
pcode.append(rDrop)
|
||||||
|
pcode.append(rDrop)
|
||||||
|
|
||||||
|
def cLoopPlus (pcode) :
|
||||||
|
if not cStack : fatal("No DO for LOOP to match")
|
||||||
|
code,slot = cStack.pop()
|
||||||
|
if code != "DO" : fatal("+LOOP preceded by %s (not DO)" % code)
|
||||||
|
pcode.append(rRgt)
|
||||||
|
pcode.append(rRgt)
|
||||||
|
pcode.append(rSwap)
|
||||||
|
pcode.append(rRot)
|
||||||
|
pcode.append(rAdd)
|
||||||
|
pcode.append(rOver)
|
||||||
|
pcode.append(rOver)
|
||||||
|
pcode.append(rSwap)
|
||||||
|
pcode.append(rLt)
|
||||||
|
pcode.append(rJz)
|
||||||
|
pcode.append(slot)
|
||||||
|
pcode.append(rDrop)
|
||||||
|
pcode.append(rDrop)
|
||||||
|
|
||||||
|
def cI (pcode) :
|
||||||
|
pcode.append(rRat)
|
||||||
|
|
||||||
|
def cJ (pcode) :
|
||||||
|
pcode.append(rRgt)
|
||||||
|
pcode.append(rRgt)
|
||||||
|
pcode.append(rRgt)
|
||||||
|
pcode.append(rDup)
|
||||||
|
pcode.append(rgtR)
|
||||||
|
pcode.append(rSwap)
|
||||||
|
pcode.append(rgtR)
|
||||||
|
pcode.append(rSwap)
|
||||||
|
pcode.append(rgtR)
|
||||||
|
|
||||||
|
def cIf (pcode) :
|
||||||
|
pcode.append(rJz)
|
||||||
|
cStack.append(("IF",len(pcode))) # flag for following Then or Else
|
||||||
|
pcode.append(0) # slot to be filled in
|
||||||
|
|
||||||
|
def cElse (pcode) :
|
||||||
|
if not cStack : fatal("No IF for ELSE to match")
|
||||||
|
code,slot = cStack.pop()
|
||||||
|
if code != "IF" : fatal("ELSE preceded by %s (not IF)" % code)
|
||||||
|
pcode.append(rJmp)
|
||||||
|
cStack.append(("ELSE",len(pcode))) # flag for following THEN
|
||||||
|
pcode.append(0) # slot to be filled in
|
||||||
|
pcode[slot] = len(pcode) # close JZ for IF
|
||||||
|
|
||||||
|
def cThen (pcode) :
|
||||||
|
if not cStack : fatal("No IF or ELSE for THEN to match")
|
||||||
|
code,slot = cStack.pop()
|
||||||
|
if code not in ("IF","ELSE") : fatal("THEN preceded by %s (not IF or ELSE)" % code)
|
||||||
|
pcode[slot] = len(pcode) # close JZ for IF or JMP for ELSE
|
||||||
|
|
||||||
|
cDict = {
|
||||||
|
':' : cColon, ';' : cSemi, 'if': cIf, 'else': cElse, 'then': cThen,
|
||||||
|
'begin': cBegin, 'until': cUntil,
|
||||||
|
'do': cDo, 'loop': cLoop, '+loop' : cLoopPlus, 'i' : cI , 'j' : cJ , 'while' : cWhile, 'repeat' : cRepeat,
|
||||||
|
}
|
||||||
|
|
||||||
|
if __name__ == "__main__" : main()
|
||||||
|
#END
|
||||||
|
EXPORT FORTH()
|
||||||
|
BEGIN
|
||||||
|
PYTHON(name);
|
||||||
|
END;
|
||||||
Loading…
Reference in a new issue