source code migrating from gitlab

c3-lang/main.c3

@@ -0,0 +1,65 @@
+module main;
+import std::io;
+
+fn int main(String[] args) {
+
+    if (args.len < 2) {
+      io::printn("Usage: HelloWorld <filename>");
+      return -1;
+    }
+    String filename = args[1];
+
+    int? answer = getSum(filename);
+    if (catch error = answer) {
+        io::printfn("error opening file: %s", error);
+        return -1;
+    }
+    io::printfn("%d", answer);
+
+
+    return 0;
+}
+
+fn int? getSum(String filename) {
+    File? file = file::open(filename, "r")!;
+
+    defer (void)file.close();
+
+    int sum = 0;
+
+    while (try line = io::treadline(&file)) {
+        char first = getFirst(line);
+        char last = getLast(line);
+        String digits = {first, last};
+        int? number = digits.to_int();
+        if (catch error = number) {
+            io::printfn("Error converting to number: %s", error);
+            continue;
+        }
+        sum += number;
+    }
+    return sum;
+}
+
+fn char getLast(String line) {
+    char last;
+    int length = line.len - 1;
+    for (int i=length; i>=0; i--) {
+        if (ascii::is_digit(line[i])) {
+            last = line[i];
+            break;
+        }
+    }
+    return last;
+}
+
+fn char getFirst(String line) {
+    char first;
+    foreach (ch : line) {
+        if (ascii::is_digit(ch)) {
+            first = ch;
+            break;
+        }
+    }
+    return first;
+}