lexical_analyze.py

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#                           Project : Compilateur (Python)                    #
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#                             File : lexical_analyze.py                       #
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#                   Description : Lexical analyze file and functions.         #
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#                Contributors : Corentin TROADEC & Anthony Vuillemin          #
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#                               Date : September 2018                         #
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#             IMPORT                #
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# PROJECT MODULES
from conf import *
from token import *
from utils import *

# SYSTEM MODULES
import re

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#           FUNCTIONS               #
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# Launch the lexical analyze line by line
def lexique_analyze(fullCode) :
    add_pow_function(True)
    # Index line
    num_line = 1
    # For each lines
    for test_code in fullCode:
        DEBUG_MSG("CURRENT CODE (Line : "+str(num_line)+") : "+test_code[:-1],"LINE") #WARNING -1 test
        # Read line and build token
        lexique_analyze_line(test_code,num_line)
        # Next line
        num_line = num_line + 1
    tab_token.append(Token("toke_eop",0,0))

# Fill the token tab
def lexique_analyze_line(code,num_line) :

    i = 0
    while i < len(code) : #for each char in expression

        current_char = code[i]

        # Char is a comment
        if(current_char == '#'):
            break;

        # Char is a space
        if(current_char == " " or current_char == "\n" or current_char == "\t") :
            current_toke = Token(None,None,None);


        # Char recognized (ONE CHAR)
        elif(current_char in hashmap_toke) :
            current_toke = Token(hashmap_toke[current_char],num_line,i)


        # Other char
        else :

            # Get the complete expression (ex : a word, an number or a keyword)
            word,rank = check_identifier(code[i:])

            # If keyword found
            if word in hashmap_toke :
                current_toke = Token(hashmap_toke[word],num_line,i)

            # If number found
            elif RepresentsInt(word) :
                current_toke = Token("toke_const",num_line,i)
                current_toke.val = int(word)

            # Char unknow --> COMPILATION ERROR
            elif re.match(r"[a-zA-Z0-9_]*",word) == False or word == "" :
                # Take only expression with number, char and underscore
                error_compilation(Token("ERR",num_line,i+1),"Incoherent char detected : "+code[i + rank]+".")

            # Is a identifier
            else :
                current_toke = Token("toke_id",num_line,i)
                current_toke.val = word

            # Go to the next block
            i = i + rank - 1


        # Expression found is a keyword with two char
        if(i+1 < len(code) ):
            if(str(current_char + code[i+1]) in hashmap_toke) :
                current_toke = Token(hashmap_toke[str(current_char + code[i+1])],num_line,i)
                i = i + 1

        # Add the token found if it isn't a None token
        if(current_toke.token != None) :
            tab_token.append(current_toke)

        # Go to the next char
        i = i + 1

# Return a identifier (composed by number or/and letter)
def check_identifier(text) :
    word = ""
    i = 0
    # Regular expression
    while i < len(text) and re.match(r"^[a-zA-Z0-9_]$",text[i]) :
        word += text[i]
        i = i + 1
    return word,i

# Add in the lexical analyze the system function pow if add is true
def add_pow_function(add) :
	text = ""
	if(add) :
		text += "pow_system(a,b){if(b==0){return 1;}var res;var i;res = a;for(i = 0;i < b-1;i = i + 1){res = res * a;}return res;}"
		lexique_analyze_line(text,None)
	return text