mini-projet-automates/main.py
2021-03-23 19:02:28 +01:00

158 lines
4 KiB
Python
Executable file

rules_dict = {}
terminals_set = set()
def parse(lines):
lines = [line.strip() for line in lines]
lines = [line.split(":") for line in lines]
rules = [(line[0].strip(), line[1].strip().split(" ")) for line in lines]
for r in rules:
for right_element in r[1]:
if len(right_element) > 0 and not right_element[0].isupper():
terminals_set.add(right_element)
for i in range(0, len(rules)):
left = rules[i][0]
if left not in rules_dict:
rules_dict[left] = 0
print_includes()
print_util()
print_declarations()
print("// ---- Functions to parse terminals ----")
print_terminal_rules()
print_rules(rules)
print_main(rules)
# print(rules)
# print(rules_dict)
# print(terminals_set)
def print_declarations():
for key in rules_dict:
print(f"int parse_{key}(char* word, int pos);")
print()
def print_includes():
print("""\
#include <stdio.h>
#include <string.h>
""")
def print_util():
print("""\
void print_with_indent(int indent, char * string) {
printf("%*s%s", indent, "", string);
}
""")
def print_main(rules):
axiom = get_code(rules[0][0])
print(f"""\
int main(int argc, char* argv[]) {{
char* word;
if (argc >= 2)
word = argv[1];
else
word = "";
int value = parse_{axiom}(word, 0);
printf("%d\\n", value);
if (value == strlen(word) + 1) {{
printf("OK\\n");
}} else {{
printf("KO\\n");
}}
}}
""")
def print_rules(rules):
print("// ---- Functions to parse a non-terminal according to a rule ----")
print_unit_rules(rules)
print("// ---- Functions to parse a non-terminal by testing all rules ----")
print_global_rules()
def print_unit_rules(rules):
for i in range(0, len(rules)):
rule = rules[i]
left = rule[0]
rules_dict[left] += 1
code = get_code(left)
print(f"""\
int parse_{code}{rules_dict[left]}(char* word, int pos) {{
int totalCharParsed = 0;
int nbCharParsed;
printf("Entering {code}{rules_dict[left]}\\n");""")
for element in rule[1]:
elem_code = get_code(element)
if elem_code != "":
print(f"""
nbCharParsed = parse_{elem_code}(word, pos + totalCharParsed);
if (nbCharParsed == -1) {{
printf("Fail {elem_code} in {code}{rules_dict[left]}\\n");
return -1;
}}
totalCharParsed += nbCharParsed;""")
else:
print(f"\n printf(\"Epsilon! -> Success\\n\");")
print(f"""
printf("Success {code}{rules_dict[left]}\\n");
return totalCharParsed;
}}
""")
def print_global_rules():
for (key, value) in rules_dict.items():
code = get_code(key)
print(f"""\
int parse_{code}(char* word, int pos) {{
int nbCharParsed;
printf("Entering {key}\\n");""")
for i in range(1, value + 1):
print(f"""
nbCharParsed = parse_{code}{i}(word, pos);
if (nbCharParsed != -1) {{
return nbCharParsed;
}}""")
print("""
return -1;
}
""")
def get_code(s):
return ord(s) if len(s) == 1 and ((s < "A" or s > "Z") and (s < "a" or s > "z")) else s
def print_terminal_rules():
for t in terminals_set:
# escape \ and " in the terminal
safeT = "\\" + t if (t == '"' or t == '\\') else t
code = get_code(t)
l = len(t)
print(f"""\
int parse_{code}(char* word, int pos) {{
// Extract the next {l} chars of the word
char substr[{l+1}];
substr[0] = '\\0';
strncat(substr, &word[pos], {l});
// Compare this extracted string to the terminal,
// and check if the next char is a space or the end of the string
if (strcmp(substr, "{safeT}") == 0 && (word[pos+{l}] == ' ' || word[pos+{l}] == '\\0')) {{
print_with_indent(pos, "{safeT}\\n");
return {l+1};
}} else {{
return -1;
}}
}}
""")
if __name__ == '__main__':
with open("grammar.txt", "r") as f:
parse(f.readlines())