slowly but steadily

2025-06-17 17:01:37 +00:00 · 2019-03-12 04:35:01 +01:00
parent 8e9586783f
commit 36d54d63d5
11 changed files with 268 additions and 641 deletions
--- a/std/assembly/util/string.ts
+++ b/std/assembly/util/string.ts
@ -0,0 +1,124 @@
+export function compareImpl(str1: string, index1: usize, str2: string, index2: usize, len: usize): i32 {
+  var result: i32 = 0;
+  var ptr1 = changetype<usize>(str1) + (index1 << 1);
+  var ptr2 = changetype<usize>(str2) + (index2 << 1);
+  while (len && !(result = <i32>load<u16>(ptr1) - <i32>load<u16>(ptr2))) {
+    --len, ptr1 += 2, ptr2 += 2;
+  }
+  return result;
+}
+
+@inline export const enum CharCode {
+  PLUS = 0x2B,
+  MINUS = 0x2D,
+  DOT = 0x2E,
+  _0 = 0x30,
+  _1 = 0x31,
+  _2 = 0x32,
+  _3 = 0x33,
+  _4 = 0x34,
+  _5 = 0x35,
+  _6 = 0x36,
+  _7 = 0x37,
+  _8 = 0x38,
+  _9 = 0x39,
+  A = 0x41,
+  B = 0x42,
+  E = 0x45,
+  N = 0x4E,
+  O = 0x4F,
+  X = 0x58,
+  Z = 0x5a,
+  a = 0x61,
+  b = 0x62,
+  e = 0x65,
+  n = 0x6E,
+  o = 0x6F,
+  x = 0x78,
+  z = 0x7A
+}
+
+export function isWhiteSpaceOrLineTerminator(c: u16): bool {
+  switch (c) {
+    case 9:    // <TAB>
+    case 10:   // <LF>
+    case 13:   // <CR>
+    case 11:   // <VT>
+    case 12:   // <FF>
+    case 32:   // <SP>
+    case 160:  // <NBSP>
+    case 8232: // <LS>
+    case 8233: // <PS>
+    case 65279: return true; // <ZWNBSP>
+    default: return false;
+  }
+}
+
+/** Parses a string to an integer (usually), using the specified radix. */
+export function parse<T>(str: string, radix: i32 = 0): T {
+  var len: i32 = str.length;
+  if (!len) return <T>NaN;
+
+  var ptr = changetype<usize>(str) /* + HEAD -> offset */;
+  var code = <i32>load<u16>(ptr, HEADER_SIZE);
+
+  // determine sign
+  var sign: T;
+  if (code == CharCode.MINUS) {
+    if (!--len) return <T>NaN;
+    code = <i32>load<u16>(ptr += 2, HEADER_SIZE);
+    sign = -1;
+  } else if (code == CharCode.PLUS) {
+    if (!--len) return <T>NaN;
+    code = <i32>load<u16>(ptr += 2, HEADER_SIZE);
+    sign = 1;
+  } else {
+    sign = 1;
+  }
+
+  // determine radix
+  if (!radix) {
+    if (code == CharCode._0 && len > 2) {
+      switch (<i32>load<u16>(ptr + 2, HEADER_SIZE)) {
+        case CharCode.B:
+        case CharCode.b: {
+          ptr += 4; len -= 2;
+          radix = 2;
+          break;
+        }
+        case CharCode.O:
+        case CharCode.o: {
+          ptr += 4; len -= 2;
+          radix = 8;
+          break;
+        }
+        case CharCode.X:
+        case CharCode.x: {
+          ptr += 4; len -= 2;
+          radix = 16;
+          break;
+        }
+        default: radix = 10;
+      }
+    } else radix = 10;
+  } else if (radix < 2 || radix > 36) {
+    return <T>NaN;
+  }
+
+  // calculate value
+  var num: T = 0;
+  while (len--) {
+    code = <i32>load<u16>(ptr, HEADER_SIZE);
+    if (code >= CharCode._0 && code <= CharCode._9) {
+      code -= CharCode._0;
+    } else if (code >= CharCode.A && code <= CharCode.Z) {
+      code -= CharCode.A - 10;
+    } else if (code >= CharCode.a && code <= CharCode.z) {
+      code -= CharCode.a - 10;
+    } else break;
+    if (code >= radix) break;
+    num = (num * radix) + code;
+    ptr += 2;
+  }
+  return sign * num;
+}