Implemented expression parsing

src/build/expression/List.go

@@ -0,0 +1,41 @@
+package expression
+
+import (
+	"git.akyoto.dev/cli/q/src/build/token"
+)
+
+// List generates a list of expressions from comma separated parameters.
+func List(tokens []token.Token) []*Expression {
+	var list []*Expression
+
+	start := 0
+	groupLevel := 0
+
+	for i, t := range tokens {
+		switch t.Kind {
+		case token.GroupStart, token.ArrayStart, token.BlockStart:
+			groupLevel++
+
+		case token.GroupEnd, token.ArrayEnd, token.BlockEnd:
+			groupLevel--
+
+		case token.Separator:
+			if groupLevel > 0 {
+				continue
+			}
+
+			parameter := tokens[start:i]
+			expression := Parse(parameter)
+			list = append(list, expression)
+			start = i + 1
+		}
+	}
+
+	if start != len(tokens) {
+		parameter := tokens[start:]
+		expression := Parse(parameter)
+		list = append(list, expression)
+	}
+
+	return list
+}