tutorial: update all examples

Author: miaobyte

tutorial/01-hello/main.kv

@@ -1,7 +1,8 @@
 # 01-hello: your first kvlang program
-# Run: kvlang tutorial/01-hello/main.kv
+# Run: kvlang tutorial/01-hello/
 
 def main() -> () {
     print("hello kvlang")
 }
+
 main() -> ()

tutorial/02-vars/main.kv

@@ -1,11 +1,12 @@
 # 02-vars: variables and paths
-# Run: kvlang tutorial/02-vars/main.kv
+# Run: kvlang tutorial/02-vars/
 
 def main() -> () {
-    42 -> ./x                     // write 42 to path ./x
-    print("x =", ./x)             // read from path ./x
+    42 -> x                     // write 42 to path x
+    print("x =", x)            // read from path x
 
-    ./x + 8 -> ./y              // 42 + 8 = 50
-    print("y =", ./y)
+    x + 8 -> y                  // 42 + 8 = 50
+    print("y =", y)
 }
+
 main() -> ()

tutorial/03-arith/main.kv

@@ -1,5 +1,5 @@
 # 03-arith: arithmetic operations
-# Run: kvlang tutorial/03-arith/main.kv
+# Run: kvlang tutorial/03-arith/
 
 def main() -> () {
     print("add:", 10 + 3)          // 13
@@ -11,7 +11,6 @@ def main() -> () {
     print("pow:", pow(2, 5))       // 32
     print("sqrt:", sqrt(144))      // 12
     print("abs:", abs(-42))        // 42
-    print("max:", max(3, 7, 1))    // 7
-    print("min:", min(3, 7, 1))    // 1
 }
+
 main() -> ()

tutorial/04-func/main.kv

@@ -1,19 +1,20 @@
 # 04-func: defining and calling functions
-# Run: kvlang tutorial/04-func/main.kv
+# Run: kvlang tutorial/04-func/
 
 def add(A: int, B: int) -> (C: int) {
-    A + B -> ./C
+    A + B -> C
 }
 
 def double(x: int) -> (y: int) {
-    x * 2 -> ./y
+    x * 2 -> y
 }
 
 def main() -> () {
-    add(10, 20) -> ./a           // 30
-    print("add(10,20) =", ./a)
+    add(10, 20) -> a           // 30
+    print("add(10,20) =", a)
 
-    double(./a) -> ./b          // 60
-    print("double(add(10,20)) =", ./b)
+    double(a) -> b             // 60
+    print("double(add(10,20)) =", b)
 }
+
 main() -> ()

tutorial/05-if/main.kv

@@ -1,23 +1,24 @@
 # 05-if: conditional logic
-# Run: kvlang tutorial/05-if/main.kv
+# Run: kvlang tutorial/05-if/
 
 def abs(x: int) -> (r: int) {
     if (x < 0) {
-        -x -> ./r
+        -x -> r
     } else {
-        x -> ./r
+        x -> r
     }
 }
 
 def main() -> () {
-    abs(-5) -> ./a
-    print("abs(-5) =", ./a)      // 5
+    abs(-5) -> a
+    print("abs(-5) =", a)      // 5
 
-    abs(3) -> ./b
-    print("abs(3) =", ./b)       // 3
+    abs(3) -> b
+    print("abs(3) =", b)       // 3
 
     print("true && false =", true && false)   // false
     print("true || false =", true || false)   // true
     print("!true =", !true)                   // false
 }
+
 main() -> ()

tutorial/06-while/main.kv

@@ -1,55 +1,53 @@
 # 06-while: while loops, break, and continue
-# Run: kvlang tutorial/06-while/main.kv
+# Run: kvlang tutorial/06-while/
 
-# sum 1 + 2 + ... + n
 def sum_to(n: int) -> (total: int) {
-    0 -> ./total
-    1 -> ./i
-    while (./i <= n) {
-        ./total + ./i -> ./total
-        ./i + 1 -> ./i
+    0 -> total
+    1 -> i
+    while (i <= n) {
+        total + i -> total
+        i + 1 -> i
     }
 }
 
-# find the first multiple of 7 in [1, n]; 0 if none (demonstrates break)
 def first_div7(n: int) -> (result: int) {
-    0 -> ./result
-    1 -> ./i
-    while (./i <= n) {
-        ./i % 7 -> ./rem
-        ./rem == 0 -> ./hit
-        if (./hit) {
-            ./i -> ./result
+    0 -> result
+    1 -> i
+    while (i <= n) {
+        i % 7 -> rem
+        rem == 0 -> hit
+        if (hit) {
+            i -> result
             break
         }
-        ./i + 1 -> ./i
+        i + 1 -> i
     }
 }
 
-# sum only odd numbers in [1, n] (demonstrates continue)
 def sum_odds(n: int) -> (total: int) {
-    0 -> ./total
-    1 -> ./i
-    while (./i <= n) {
-        ./i % 2 -> ./rem
-        ./rem == 0 -> ./even
-        if (./even) {
-            ./i + 1 -> ./i
+    0 -> total
+    1 -> i
+    while (i <= n) {
+        i % 2 -> rem
+        rem == 0 -> even
+        if (even) {
+            i + 1 -> i
             continue
         }
-        ./total + ./i -> ./total
-        ./i + 1 -> ./i
+        total + i -> total
+        i + 1 -> i
     }
 }
 
 def main() -> () {
-    sum_to(10) -> ./s
-    print("sum(1..10) =", ./s)              // 55
+    sum_to(10) -> s
+    print("sum(1..10) =", s)              // 55
 
-    first_div7(20) -> ./d7
-    print("first div7 in [1,20] =", ./d7)   // 7
+    first_div7(20) -> d7
+    print("first div7 in [1,20] =", d7)   // 7
 
-    sum_odds(10) -> ./so
-    print("sum odds(1..10) =", ./so)        // 25
+    sum_odds(10) -> so
+    print("sum odds(1..10) =", so)        // 25
 }
+
 main() -> ()

tutorial/07-recursion/main.kv

@@ -1,31 +1,32 @@
 # 07-recursion: recursive functions with TCO
-# Run: kvlang tutorial/07-recursion/main.kv
+# Run: kvlang tutorial/07-recursion/
 
 def fib(n: int) -> (a: int, b: int) {
     if (n <= 1) {
-        0 -> ./a
-        1 -> ./b
+        0 -> a
+        1 -> b
     } else {
-        fib(n - 1) -> ./a, ./b
-        ./a + ./b -> ./x
-        ./b -> ./a
-        ./x -> ./b
+        fib(n - 1) -> a, b
+        a + b -> x
+        b -> a
+        x -> b
     }
 }
 
 def fact(n: int, acc: int) -> (r: int) {
     if (n <= 0) {
-        acc -> ./r
+        acc -> r
     } else {
-        fact(n - 1, acc * n) -> ./r
+        fact(n - 1, acc * n) -> r
     }
 }
 
 def main() -> () {
-    fib(10) -> ./_, ./result
-    print("fib(10) =", ./result)
+    fib(10) -> _, result
+    print("fib(10) =", result)
 
-    fact(10, 1) -> ./f
-    print("fact(10) =", ./f)     // 3628800
+    fact(10, 1) -> f
+    print("fact(10) =", f)     // 3628800
 }
+
 main() -> ()

tutorial/08-algo/classify.kv

@@ -7,23 +7,23 @@
 
 def classify(score:int) -> (grade:string) {
     if (score >= 90) {
-        "A" -> ./grade
+        "A" -> grade
     } else {
         if (score >= 80) {
-            "B" -> ./grade
+            "B" -> grade
         } else {
             if (score >= 70) {
-                "C" -> ./grade
+                "C" -> grade
             } else {
                 if (score >= 60) {
-                    "D" -> ./grade
+                    "D" -> grade
                 } else {
-                    "F" -> ./grade
+                    "F" -> grade
                 }
             }
         }
     }
 }
 
-classify(85) -> ./g
-print("grade =", ./g)
+classify(85) -> g
+print("grade =", g)

tutorial/08-algo/collatz.kv

@@ -6,19 +6,19 @@
 #   steps = 111
 
 def collatz(n:int) -> (steps:int) {
-    0 -> ./steps
+    0 -> steps
     while (n > 1) {
-        n % 2 -> ./mod
-        ./mod == 0 -> ./even
-        if (./even) {
+        n % 2 -> mod
+        mod == 0 -> even
+        if (even) {
             n / 2 -> n
         } else {
-            n * 3 -> ./t
-            ./t + 1 -> n
+            n * 3 -> t
+            t + 1 -> n
         }
-        ./steps + 1 -> ./steps
+        steps + 1 -> steps
     }
 }
 
-collatz(27) -> ./ans
-print("steps =", ./ans)
+collatz(27) -> ans
+print("steps =", ans)

tutorial/08-algo/factorial.kv

@@ -6,13 +6,13 @@
 #   fact = 3628800
 
 def factorial(n:int) -> (result:int) {
-    1 -> ./result
-    1 -> ./i
-    while (./i <= n) {
-        ./result * ./i -> ./result
-        ./i + 1 -> ./i
+    1 -> result
+    1 -> i
+    while (i <= n) {
+        result * i -> result
+        i + 1 -> i
     }
 }
 
-factorial(10) -> ./ans
-print("fact =", ./ans)
+factorial(10) -> ans
+print("fact =", ans)