Question

Totally new to python, and i want to do the following:

I have this code:

def assem(myFile):
print "Hello ,World!" 
import myParser
from myParser import Parser
import code
import symboleTable
from symboleTable import SymboleTable


newFile = "Prog.hack"
output = open(newFile, 'w')
input = open(myFile, 'r')


prsr=Parser(input)
while prsr.hasMoreCommands():
    str = "BLANK"
    if(parser.commandType() == Parser.C_COMMAND):
        str="111"+code.comp(prsr.comp())+code.dest(prsr.dest())+code.jump(prsr.jump())+"\n"

    output.write(str)
    prsr.advance()

checked the indentation, its ok,its a bit messy over here.

this program needs to run from console and receive a file named Add.asm

what is the console command to make it run?

tried :

  python assembler.py Add.asm

did not work.

any idea?

Answer 1

optparse is indeed what you will need for more advanced cl options. However, you could python assembler.py <filename> with a simple if __name__ == "__main__" block. In lieu of argparse or optparse, you can use sys.argv[1] for a single simple argument to the script.

def assem(myFile):
    print "Hello ,World!" 
    import myParser
    from myParser import Parser
    import code
    import symboleTable
    from symboleTable import SymboleTable

    newFile = "Prog.hack"
    output = open(newFile, 'w')
    input = open(myFile, 'r')
    prsr = Parser(input)

    while prsr.hasMoreCommands():
        str = "BLANK"
        if(parser.commandType() == Parser.C_COMMAND):
            str= "111" + code.comp(prsr.comp()
                ) + code.dest(prsr.dest()) + code.jump(prsr.jump()
                ) + "\n"

        output.write(str)
        prsr.advance()

if __name__ == "__main__":
    import sys
    assem(sys.argv[1])

You’ll also want to google python string formatting and find links like http://docs.python.org/library/stdtypes.html#string-formatting