Simplified some Rust code by using slice.chunks().

rust-no-heap/src/lib.rs

@@ -1111,21 +1111,12 @@ impl<'a> QrSegment<'a> {
 	/// 
 	/// Panics if the string contains non-digit characters.
 	pub fn make_numeric(text: &str, buf: &'a mut [u8]) -> Self {
+		assert!(text.bytes().all(|b| (b'0' ..= b'9').contains(&b)), "String contains non-numeric characters");
 		let mut bb = BitBuffer::new(buf);
-		let mut accumdata: u32 = 0;
-		let mut accumcount: u8 = 0;
-		for b in text.bytes() {
-			assert!((b'0' ..= b'9').contains(&b), "String contains non-numeric characters");
-			accumdata = accumdata * 10 + u32::from(b - b'0');
-			accumcount += 1;
-			if accumcount == 3 {
-				bb.append_bits(accumdata, 10);
-				accumdata = 0;
-				accumcount = 0;
-			}
-		}
-		if accumcount > 0 {  // 1 or 2 digits remaining
-			bb.append_bits(accumdata, accumcount * 3 + 1);
+		for chunk in text.as_bytes().chunks(3) {
+			let data: u32 = chunk.iter().fold(0u32,
+				|acc, &b| acc * 10 + u32::from(b - b'0'));
+			bb.append_bits(data, (chunk.len() as u8) * 3 + 1);
 		}
 		QrSegment::new(QrSegmentMode::Numeric, text.len(), bb.data, bb.length)
 	}
@@ -1139,21 +1130,10 @@ impl<'a> QrSegment<'a> {
 	/// Panics if the string contains non-encodable characters.
 	pub fn make_alphanumeric(text: &str, buf: &'a mut [u8]) -> Self {
 		let mut bb = BitBuffer::new(buf);
-		let mut accumdata: u32 = 0;
-		let mut accumcount: u8 = 0;
-		for c in text.chars() {
-			let i: usize = ALPHANUMERIC_CHARSET.find(c)
-				.expect("String contains unencodable characters in alphanumeric mode");
-			accumdata = accumdata * 45 + u32::try_from(i).unwrap();
-			accumcount += 1;
-			if accumcount == 2 {
-				bb.append_bits(accumdata, 11);
-				accumdata = 0;
-				accumcount = 0;
-			}
-		}
-		if accumcount > 0 {  // 1 character remaining
-			bb.append_bits(accumdata, 6);
+		for chunk in text.as_bytes().chunks(2) {
+			let data: u32 = chunk.iter().fold(0u32, |acc, &b| acc * 45 + u32::try_from(
+				ALPHANUMERIC_CHARSET.find(char::from(b)).expect("String contains unencodable characters in alphanumeric mode")).unwrap());
+			bb.append_bits(data, (chunk.len() as u8) * 5 + 1);
 		}
 		QrSegment::new(QrSegmentMode::Alphanumeric, text.len(), bb.data, bb.length)
 	}

rust/src/lib.rs

@@ -985,22 +985,13 @@ impl QrSegment {
 	/// 
 	/// Panics if the string contains non-digit characters.
 	pub fn make_numeric(text: &str) -> Self {
+		assert!(text.bytes().all(|b| (b'0' ..= b'9').contains(&b)), "String contains non-numeric characters");
 		let mut bb = BitBuffer(Vec::with_capacity(
 			text.len().checked_mul(3).unwrap().checked_add(text.len().div_ceil(3)).unwrap()));
-		let mut accumdata: u32 = 0;
-		let mut accumcount: u8 = 0;
-		for b in text.bytes() {
-			assert!((b'0' ..= b'9').contains(&b), "String contains non-numeric characters");
-			accumdata = accumdata * 10 + u32::from(b - b'0');
-			accumcount += 1;
-			if accumcount == 3 {
-				bb.append_bits(accumdata, 10);
-				accumdata = 0;
-				accumcount = 0;
-			}
-		}
-		if accumcount > 0 {  // 1 or 2 digits remaining
-			bb.append_bits(accumdata, accumcount * 3 + 1);
+		for chunk in text.as_bytes().chunks(3) {
+			let data: u32 = chunk.iter().fold(0u32,
+				|acc, &b| acc * 10 + u32::from(b - b'0'));
+			bb.append_bits(data, (chunk.len() as u8) * 3 + 1);
 		}
 		QrSegment::new(QrSegmentMode::Numeric, text.len(), bb.0)
 	}
@@ -1015,21 +1006,10 @@ impl QrSegment {
 	pub fn make_alphanumeric(text: &str) -> Self {
 		let mut bb = BitBuffer(Vec::with_capacity(
 			text.len().checked_mul(5).unwrap().checked_add(text.len().div_ceil(2)).unwrap()));
-		let mut accumdata: u32 = 0;
-		let mut accumcount: u32 = 0;
-		for c in text.chars() {
-			let i: usize = ALPHANUMERIC_CHARSET.find(c)
-				.expect("String contains unencodable characters in alphanumeric mode");
-			accumdata = accumdata * 45 + u32::try_from(i).unwrap();
-			accumcount += 1;
-			if accumcount == 2 {
-				bb.append_bits(accumdata, 11);
-				accumdata = 0;
-				accumcount = 0;
-			}
-		}
-		if accumcount > 0 {  // 1 character remaining
-			bb.append_bits(accumdata, 6);
+		for chunk in text.as_bytes().chunks(2) {
+			let data: u32 = chunk.iter().fold(0u32, |acc, &b| acc * 45 + u32::try_from(
+				ALPHANUMERIC_CHARSET.find(char::from(b)).expect("String contains unencodable characters in alphanumeric mode")).unwrap());
+			bb.append_bits(data, (chunk.len() as u8) * 5 + 1);
 		}
 		QrSegment::new(QrSegmentMode::Alphanumeric, text.len(), bb.0)
 	}