src/runMain/kotlin/Semantic.kt


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

import TokenType.*
import exceptions.*

class Semantic {
    /**
     * Checks and validates whether the code complies with the semantic rules
     * TODO: Handle scopes via { and }
     */
    fun check(statements: MutableList<MutableList<Token>>): Boolean {
        val variables = mutableListOf<String>()
        statements.forEach { statement ->
            if (statement[0].type == Variable) {
                if (nextNonEmpty(statement, 0).type == Assignment) {
                    variables.add(statement[0].content)
                }
            }

            for (token in statement) {
                if (token.type == Variable && token.content !in variables) {
                    throw SemanticError("Undeclared variable", token.content)
                }
            }
        }
        return true
    }
}