Add two nodes for substring

Author: daniil.loban

node-graph/gcore/src/logic.rs

@@ -120,3 +120,20 @@ async fn switch<T, C: Send + 'n + Clone>(
 		if_false.eval(ctx).await
 	}
 }
+
+// Get an indexed part of string whitch separated a specified delimeter ("1;2;3" e.t.c.)
+#[node_macro::node(category("Text"))]
+fn substring_by_index(_: impl Ctx, #[implementations(String)] string: String, delimeter: String, index: u32) -> String {
+	let idx = index as usize;
+	let parts: Vec<&str> = string.split(&delimeter).collect();
+	if idx < parts.len() { parts[idx].to_string() } else { String::new() }
+}
+
+// Get amount substrings like ";" in string (useful for check max index in substring_by_index)
+#[node_macro::node(category("Text"))]
+fn count_substring(_: impl Ctx, #[implementations(String)] string: String, substring: String) -> f64 {
+	if substring.is_empty() {
+		return 0.0;
+	}
+	string.matches(&substring).count() as f64
+}