Allow to input of negative unsigned numbers

src/core/components/BinaryString.tsx

@@ -9,6 +9,7 @@ export type BinaryStringViewProps = {
     className?: string;
     disableHighlight?: boolean,
     signBitIndex?: number,
+    integerBitSize?: number
 };
 
 export type FlipBitEventArg = {
@@ -57,13 +58,17 @@ export default class BinaryStringView extends React.Component<BinaryStringViewPr
         const css = allowFlipBits ? ' flipable' : ''
 
         const disableHighlight = this.props.disableHighlight || false;
+        const firstBitIndex = this.props.integerBitSize != null 
+            ?  bitChars.length - this.props.integerBitSize
+            : -1;
 
         return bitChars.map((c, i) => {
 
             var className = c == '1' ? `one${css}` : `zero${css}`;
             var tooltip = '';
 
-            const isExtra = i < (this.props.signBitIndex || 0);
+            
+            const isExtra = i < firstBitIndex;
             if (isExtra)
                 className += ' extra-bit';
 

src/core/const.ts

@@ -1,8 +1,9 @@
-
+const UINT8_MAX_VALUE = 255;
+const UINT16_MAX_VALUE = 65535
 const INT32_MAX_VALUE = 2147483647;
 const INT32_MIN_VALUE = -2147483648;
 const UINT32_MAX_VALUE = 4294967295;
 const INT64_MAX_VALUE = BigInt("9223372036854775807");
 const INT64_MIN_VALUE = BigInt("-9223372036854775808");
 const UINT64_MAX_VALUE = BigInt("18446744073709551615");
-export {INT32_MAX_VALUE, INT32_MIN_VALUE, INT64_MAX_VALUE, INT64_MIN_VALUE, UINT32_MAX_VALUE, UINT64_MAX_VALUE};
+export {INT32_MAX_VALUE, INT32_MIN_VALUE, INT64_MAX_VALUE, INT64_MIN_VALUE, UINT32_MAX_VALUE, UINT64_MAX_VALUE, UINT8_MAX_VALUE, UINT16_MAX_VALUE };

src/expression/components/BitwiseResultView.tsx

@@ -126,6 +126,7 @@ class ExpressionElementTableRow extends React.Component<ExpressionElementRowProp
                     binaryString={bin}
                     allowFlipBits={allowFlipBits}
                     signBitIndex={signBitIndex}
+                    integerBitSize={this.scalar.value.maxBitSize}
                     onBitClicked={args => this.onBitClicked(args)} />
             </td>
             <td className="other">{this.getAlternative()}</td>

src/expression/numberParser.test.ts

@@ -1,6 +1,7 @@
 import exp from 'constants';
 import { asIntN } from '../core/utils';
 import {numberParser, ParsedNumber} from './numberParser';
+import { UINT16_MAX_VALUE, UINT32_MAX_VALUE, UINT64_MAX_VALUE, UINT8_MAX_VALUE } from '../core/const';
 
 describe("parser", () => {
 
@@ -124,10 +125,6 @@ describe("parser", () => {
         //expect(v2).toEqual(v);
     });
 
-    it('cannot parse negative usigned', () => {
-       expect(() => numberParser.parse('-1u')).toThrowError("-1u unsigned integer cannot be negative");
-    });
-
     it('parses usigned single', () => {
         var v =  numberParser.parse('1us')?.value
         expect(v?.maxBitSize).toBe(16);
@@ -164,4 +161,23 @@ describe("parser", () => {
         //var v2 =  numberParser.parse('1i16')?.value
         //expect(v2?.num()).toEqual(v?.num());
     });
+
+    it('allows negative unsigned for the sake of cimplicity', () => {
+        
+        const ubyte = numberParser.parse("-1ub").value;
+        expect(ubyte.num()).toBe(UINT8_MAX_VALUE);
+        expect(ubyte.maxBitSize).toBe(8);
+
+        const ushort = numberParser.parse("-1us").value;
+        expect(ushort.num()).toBe(UINT16_MAX_VALUE);
+        expect(ushort.maxBitSize).toBe(16);
+
+        const uint = numberParser.parse("-1u").value;
+        expect(uint.num()).toBe(UINT32_MAX_VALUE);
+        expect(uint.maxBitSize).toBe(32);
+
+        const ulong = numberParser.parse("-1ul").value;
+        expect(ulong.value).toBe(UINT64_MAX_VALUE);
+        expect(ulong.maxBitSize).toBe(64);
+    });
 });

src/expression/numberParser.ts

@@ -52,11 +52,17 @@ function parseInteger(input : string, numberPart: string, suffix: string)  : Int
     let num = BigInt(numberPart);
     const signed = !suffix.startsWith('u');
 
-    if(!signed && isNegative)
-        throw new Error(input + " unsigned integer cannot be negative");
+    const bitSize = getSizeBySuffix(suffix, num, signed);
+    const newValue = isNegative  ? -num : num;
 
-    const size = getSizeBySuffix(suffix, num, signed);
-    return new Integer(isNegative  ? -num : num, size, signed);
+    if(!signed && isNegative)
+    {
+        const signed = new Integer(newValue, bitSize, true);
+        const bin = "0b" + signed.toString(2);
+        return  Integer.unsigned(BigInt(bin), bitSize);
+    }
+
+    return new Integer(newValue, bitSize, signed);
 }
 
 function getSizeBySuffix(suffix: string, value : bigint, signed: boolean) {

src/index.css

@@ -71,7 +71,7 @@ a.hashLink { font-size: 1.1em;}
 
 .cur { color: lightgray; }
 
-.extra-bit { opacity: 0.2;}
+.extra-bit { opacity: 0.3;}
 
 button { border: none; text-decoration: underline;}