forked from simoneguidi94/gopapageno
-
Notifications
You must be signed in to change notification settings - Fork 0
/
check.go
39 lines (32 loc) · 708 Bytes
/
check.go
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
package generator
func inferTokens(rules []rule) (stringSet, stringSet) {
nonterminals := newStringSet()
tokens := newStringSet()
for _, rule := range rules {
if !nonterminals.Contains(rule.LHS) {
nonterminals.Add(rule.LHS)
}
for _, token := range rule.RHS {
if !tokens.Contains(token) {
tokens.Add(token)
}
}
}
terminals := newStringSet()
for _, token := range tokens {
if !nonterminals.Contains(token) {
terminals.Add(token)
}
}
nonterminals.Add("_EMPTY")
terminals.Add("_TERM")
return nonterminals, terminals
}
func checkAxiomUsage(rules []rule, axiom string) bool {
for _, rule := range rules {
if rule.LHS == axiom {
return true
}
}
return false
}