Int Lexer_ParseDigit(Lexer lexer, Bool isFirstContentOnLine)
{
const Byte *src = lexer->src;
const Byte *start, *digitsEnd;
Token token = lexer->token;
UInt64 value;
String suffix;
START_TOKEN(src - 1);
start = src - 1;
// Decimal integer, or possibly a real value (if we find a '.').
if (!ParseDecimalInteger(lexer, &value)) {
lexer->token->text = IllegalDecimalIntegerMessage;
return END_TOKEN(TOKEN_ERROR);
}
digitsEnd = src = lexer->src;
if (src < lexer->end && *src == '.' && (src + 1 == lexer->end || src[1] != '.')) {
// Found a '.' (and it's not part of a ".."), so rewind back and re-parse this as a real or float value.
lexer->src = start;
return Lexer_ParseReal(lexer, isFirstContentOnLine);
}
else {
// Collected a whole octal value, so finish it.
suffix = CollectAlphanumericSuffix(lexer);
if (!EnsureEndOfNumber(lexer)) return END_TOKEN(TOKEN_ERROR);
END_TOKEN(TOKEN_INTEGER32);
return ProcessIntegerValue(lexer, value, String_Create(start, digitsEnd - start), suffix);
}
}
/// <summary>
/// Having seen a dot '.' in the input, parse one of the following four kinds of tokens:
///
/// . (dot)
/// .. (range)
/// ... (ellipsis)
/// .123 (real value)
///
/// We need to figure out which of these four cases we're dealing with, and decode
/// the input accordingly into the correct kind of token.
/// </summary>
/// <param name="lexer">The lexical analyzer.</param>
/// <param name="isFirstContentOnLine">Whether this token is the first non-whitespace non-comment content on its line.</param>
/// <returns>The next token that was found in the input.</returns>
Int Lexer_ParseDot(Lexer lexer, Bool isFirstContentOnLine)
{
const Byte *src = lexer->src;
const Byte *end = lexer->end;
Token token = lexer->token;
Byte ch;
if (src >= end)
return SIMPLE_TOKEN(src - 1, TOKEN_DOT);
if ((ch = *src) == '.') {
src++;
// Two dots, so range or ellipsis.
if (src < end && (ch = *src) == '.') {
src++;
// Three dots, so ellipsis.
return SIMPLE_TOKEN(src - 3, TOKEN_DOTDOTDOT);
}
else return SIMPLE_TOKEN(src - 2, TOKEN_DOTDOT);
}
if (ch >= '0' && ch <= '9') {
// We got numeric digits after the dot, so this is actually a real value, not a dot operator.
lexer->src--;
return Lexer_ParseReal(lexer, isFirstContentOnLine);
}
return SIMPLE_TOKEN(src - 1, TOKEN_DOT);
}
Int Lexer_ParseZero(Lexer lexer, Bool isFirstContentOnLine)
{
const Byte *src = lexer->src;
const Byte *end = lexer->end;
const Byte *start, *digitsEnd;
Token token = lexer->token;
Byte ch;
UInt64 value;
String suffix;
START_TOKEN(src - 1);
start = src - 1;
if (src < end && ((ch = *src) == 'x' || ch == 'X')) {
// Hexadecimal integer, or possibly a zero byte.
src++;
if (src >= end || !(((ch = *src) >= '0' && ch <= '9') || (ch >= 'a' && ch <= 'f') || (ch >= 'A' && ch <= 'F'))) {
// Not an error; this is decimal zero, as a byte.
lexer->src = src;
if (!EnsureEndOfNumber(lexer)) {
lexer->token->text = String_FormatString(IllegalNumericSuffixMessage, String_Format("x%c", ch));
return END_TOKEN(TOKEN_ERROR);
}
END_TOKEN(TOKEN_INTEGER32);
return ProcessIntegerValue(lexer, 0, ZeroString, LowercaseXString);
}
else {
// This is a hexadecimal integer.
lexer->src = src;
if (!ParseHexadecimalInteger(lexer, &value)) {
lexer->token->text = IllegalHexadecimalIntegerMessage;
return END_TOKEN(TOKEN_ERROR);
}
digitsEnd = src = lexer->src;
suffix = CollectAlphanumericSuffix(lexer);
if (!EnsureEndOfNumber(lexer)) {
lexer->token->text = String_FormatString(IllegalNumericSuffixMessage, String_Format("%c", *lexer->src));
return END_TOKEN(TOKEN_ERROR);
}
END_TOKEN(TOKEN_INTEGER32);
return ProcessIntegerValue(lexer, value, String_Create(start, digitsEnd - start), suffix);
}
}
else {
// Octal integer, or possibly a real value (if we find a '.').
if (!ParseOctalInteger(lexer, &value)) {
lexer->token->text = IllegalOctalIntegerMessage;
return END_TOKEN(TOKEN_ERROR);
}
digitsEnd = src = lexer->src;
if (src < lexer->end && *src == '.' && (src+1 >= lexer->end || src[1] != '.')) {
// Found a '.' (and it's not part of a ".."), so rewind back and re-parse this as a real or float value.
lexer->src = start;
return Lexer_ParseReal(lexer, isFirstContentOnLine);
}
else {
// Collected a whole octal value, so finish it.
suffix = CollectAlphanumericSuffix(lexer);
if (!EnsureEndOfNumber(lexer)) {
lexer->token->text = String_FormatString(IllegalNumericSuffixMessage, String_Format("%c", *lexer->src));
return END_TOKEN(TOKEN_ERROR);
}
END_TOKEN(TOKEN_INTEGER32);
return ProcessIntegerValue(lexer, value, String_Create(start, digitsEnd - start), suffix);
}
}
}
