migrate to new mutable decl syntax

std/strmap/strmap.hon

@@ -20,8 +20,8 @@ init proc($V type, $N usize, $entries [N]Pair(V)) StringMap(V) {
         compile_error!("static string map has too many entries")
     }
 
-    keys [N]mut []u8 = undefined
-    values [N]mut V = undefined
+    keys [N]mut []u8 := undefined
+    values [N]mut V := undefined
 
     # assert no duplicate keys
     for entries |entry, i| {
@@ -38,7 +38,7 @@ init proc($V type, $N usize, $entries [N]Pair(V)) StringMap(V) {
     }
 
     if N == 0 {
-        len_indexes [0]u32 = undefined
+        len_indexes [0]u32 := undefined
         return StringMap(V){
             keys = keys[..],
             values = values[..],
@@ -52,7 +52,7 @@ init proc($V type, $N usize, $entries [N]Pair(V)) StringMap(V) {
     for 1..N |i| {
         key :: keys[i]
         value :: values[i]
-        j usize = i
+        j := i
         while j > 0 and keys[j - 1].len > key.len : j -= 1 {
             keys[j] = keys[j - 1]
             values[j] = values[j - 1]
@@ -63,8 +63,8 @@ init proc($V type, $N usize, $entries [N]Pair(V)) StringMap(V) {
 
     min_len u32 :: u32(keys[0].len)
     max_len u32 :: u32(keys[N - 1].len)
-    len_indexes [usize(max_len) + 1]mut u32 = undefined
-    entry_index usize = 0
+    len_indexes [usize(max_len) + 1]mut u32 := undefined
+    entry_index usize := 0
     for 0..=usize(max_len) |length| {
         while entry_index < N and keys[entry_index].len < length : entry_index += 1 {}
         len_indexes[length] = u32(entry_index)
@@ -82,10 +82,10 @@ init proc($V type, $N usize, $entries [N]Pair(V)) StringMap(V) {
 get proc($V type, map @StringMap(V), key []u8) ?V {
     if (map.keys.len == 0 or key.len > maxval!(u32)) return null
 
-    length u32 = u32(key.len)
+    length := u32(key.len)
     if (length < map.min_len or length > map.max_len) return null
 
-    idx usize = usize(map.len_indexes[usize(length)])
+    idx := usize(map.len_indexes[usize(length)])
     while idx < map.keys.len : idx += 1 {
         candidate :: map.keys[idx]
         if (candidate.len != key.len) return null # key not found