C# Класс Loyc.Syntax.ParseHelpers

Gets the integer value for the specified digit, where 'A' maps to 10 and 'Z' maps to 35, or -1 if the character is not a digit or letter.

Gets the integer value for the specified hex digit, or -1 if the character is not a hex digit.

Returns a string with any spaces and tabs removed from the beginning.

Only ' ' and '\t' are treated as spaces.

Parses a string to a double-precision float, returning NaN on failure or an infinity value on overflow.

Parses a string to a single-precision float, returning NaN on failure or an infinity value on overflow.

Parses the parts of a floating-point string. See the other overload for details.

This method is a wrapper around the other overload that combines the 'exponentBaseR' parameter with 'exponentBase2' or 'exponentBase10' depending on the radix. For example, when radix=10, this method adds exponentBaseR to exponentBase10.

Low-level method that identifies the parts of a float literal of arbitrary base (typically base 2, 10, or 16) with no prefix or suffix, such as 2.Cp0 (which means 2.75 in base 16).

The syntax required is ( '+'|'-' )? ( Digits ('.' Digits?)? | '.' Digits ) ( ('p'|'P') ('-'|'+')? DecimalDigits+ )? ( ('e'|'E') ('-'|'+')? DecimalDigits+ )? where Digits refers to one or more digits in the requested base, possibly including underscores or spaces if the flags allow it; similarly, DecimalDigits refers to base-10 digits and is also affected by the flags. Returns false if there was an error interpreting the input. To keep the parser relatively simple, it does not roll back in case of error the way the int parser does. For example, given the input "23p", the 'p' is consumed and causes the method to return false, even though the parse could have been successful if it had ignored the 'p'.

A simple method to parse a sequence of hex digits, without overflow checks or other features supported by methods like TryParseInt(string, ref int, out int, int, bool).

A simple method to parse a sequence of hex digits, without overflow checks or other features supported by methods like TryParseInt(string, ref int, out int, int, bool).

Tries to parse a string to an integer. Unlike Int32.TryParse(string, out int), this method allows parsing to start at any point in the string, it allows non-numeric data after the number, and it can parse numbers that are not in base 10.

This method never throws. If parsing fails, index is left unchanged, except that spaces are still skipped if you set the skipSpaces flag. If base>36, parsing can succeed but digits above 35 (Z) cannot occur in the output number. If the input number cannot fit in 'result', the return value is false but index increases anyway, and 'result' is a bitwise truncated version of the number. When parsing input such as "12.34", the parser stops and returns true at the dot (with a result of 12 in this case).

Tries to parse a string to an unsigned integer.

This method never throws. It shrinks the slice s as it parses, so if parsing fails, s[0] will be the character at which parsing fails. If base>36, parsing can succeed but digits above 35 (Z) cannot be represented in the input string. If the number cannot fit in result, the return value is false and the method's exact behavior depends on whether you used ParseNumberFlag.StopBeforeOverflow. When parsing input such as "12.34", the parser stops and returns true at the dot (with a result of 12 in this case).

Unescapes a string that uses C-style escape sequences, e.g. "\\\n\\\r" becomes "\n\r".

See UnescapeChar(ref UString, ref EscapeC) for details.

Unescapes a string that uses C-style escape sequences, e.g. "\\\n\\\r" becomes "\n\r".

Unescapes a single character of a string. Returns the first character if it is not a backslash, or \ if it is a backslash but no escape sequence could be discerned.

This function also decodes (non-escaped) surrogate pairs. Code points with 5 or 6 digits such as \u1F4A9 are supported. \x escapes must be two digits and set the EscapeC.BackslashX flag. \u escapes must be 4 to 6 digits. If a \u escape has more than 4 digits, the EscapeC.HasLongEscapes flag is set. Invalid 6-digit escapes like \u123456 are "made valid" by being treated as 5 digits (the largest valid escape is \u10FFFF.) Supported escapes: \u \x \\ \n \r \0 \' \" \` \t \a \b \f \v