Token Validation

Token validation functions for lexical analysis. More...

Macros
#define	min(x, y)
#define	max(x, y)

Functions
bool	chk_keywd (const char *const value)
	Checks if the given value is a C programming language keyword.
bool	chk_oprtr (const char *const value)
	Checks if the given value is a valid C operator.
bool	chk_sprtr (const char value)
	Checks if the given character is a valid separator.
bool	chk_punct (const char *const value)
	Checks if the given value is a punctuation character.
bool	chk_numlt (const char *const value)
	Checks if the given value is a valid numerical literal.
bool	chk_flolt (const char *const value)
	Checks if the given value is a valid floating-point literal.
bool	chk_chrlt (const char *const value)
	Checks if the given value is a valid character literal.
bool	chk_strlt (const char *const value)
	Checks if the given value is a valid string literal.
bool	chk_idnfr (const char *const value)
	Checks if the given value is a valid identifier.
bool	chk_prpop (const char *const value)
	Checks if the given value is a preprocessor directive.

Detailed Description

Token validation functions for lexical analysis.

Provides pattern-matching functions that identify:

• Language keywords (e.g., if, while)
• Operators and punctuation (e.g., +, ;)
• Literals (numeric, string, character)
• Identifiers and preprocessor directives

Used during tokenization to classify raw lexemes into specific token types. All functions are case-sensitive and follow standard C syntax rules.

Note

These are pure validation functions - they don't modify input or handle memory allocation.

Macro Definition Documentation

max

#define max	(		x,
			y )

Value:

((x) > (y) ? (x) : (y))

min

#define min	(		x,
			y )

Value:

((x) < (y) ? (x) : (y))

Function Documentation

chk_chrlt()

bool chk_chrlt

(

const char *const

value

)

Checks if the given value is a valid character literal.

This function checks whether the provided string represents a valid character literal in C/C++. A valid character literal consists of exactly one character enclosed in single quotes (e.g., ‘'a’,''), or it may be a special character (e.g.,'
','\'`) represented with an escape sequence enclosed in single quotes.

Parameters

value

A constant pointer to the string to be checked.

Returns

true if the value is a valid character literal, false otherwise.

Note

A valid character literal must meet one of the following conditions:

• It is exactly 3 characters long and starts and ends with a single quote (e.g., ‘'a’).
• It is exactly 4 characters long, starts with a single quote, has an escape sequence in the middle (e.g.,'\'), and ends with a single quote (e.g.,'
  'or'\'`).

chk_flolt()

bool chk_flolt

(

const char *const

value

)

Checks if the given value is a valid floating-point literal.

This function verifies if the provided string represents a valid floating-point literal. A valid floating-point literal can have a decimal point and may include an optional exponent part (e.g., 3.14, 1e10, 2.5e-3). Leading and trailing spaces are ignored during the check. The function will return true if the string represents a valid floating-point number, and false otherwise.

Parameters

value

A constant pointer to the string to be checked.

Returns

true if the value is a valid floating-point literal, false otherwise.

Note

The function uses strtold to attempt conversion of the string to a long double value. It considers spaces and ignores quotes (if any).

chk_idnfr()

bool chk_idnfr

(

const char *const

value

)

Checks if the given value is a valid identifier.

This function checks whether the provided string is a valid identifier in C/C++. A valid identifier must:

• Begin with a letter (a-z, A-Z) or an underscore (_).
• Subsequent characters can be letters, digits (0-9), underscores (_), or periods (.).
• If periods are present, they must separate valid identifiers (i.e., they should not appear consecutively or at the start/end of the string).

Parameters

value

A constant pointer to the string to be checked.

Returns

true if the value is a valid identifier, false otherwise.

Note

A valid identifier is typically used for variable names, function names, or other symbols in C/C++ programming. This function allows for periods (.) in the identifier but enforces the rule that periods must separate valid identifier segments.

chk_keywd()

bool chk_keywd

(

const char *const

value

)

Checks if the given value is a C programming language keyword.

This function checks if the provided string matches any of the 31 reserved keywords in the C language. It compares the input string with a predefined list of C keywords and returns a boolean indicating whether the value is a valid keyword or not.

Parameters

value

A constant pointer to the string to be checked.

Returns

true if the value matches a C keyword, false otherwise.

Note

The function performs a case-sensitive comparison with the list of C keywords.

chk_numlt()

bool chk_numlt

(

const char *const

value

)

Checks if the given value is a valid numerical literal.

This function verifies if the provided string represents a valid numerical literal. A valid numerical literal consists of an optional sign followed by a sequence of digits. Leading and trailing spaces are ignored during the check. The function will return true if the string represents a valid number, and false otherwise.

Parameters

value

A constant pointer to the string to be checked.

Returns

true if the value is a valid numerical literal, false otherwise.

Note

The function uses strtoll to attempt conversion of the string to a long long integer. It considers spaces and ignores quotes (if any).

chk_oprtr()

bool chk_oprtr

(

const char *const

value

)

Checks if the given value is a valid C operator.

This function checks if the provided string matches any of the common operators in C. It compares the input string with a predefined list of C operators (including arithmetic, logical, comparison, and assignment operators) and returns a boolean indicating whether the value is a valid operator or not.

Parameters

value

A constant pointer to the string to be checked.

Returns

true if the value matches a C operator, false otherwise.

Note

The function performs a case-sensitive comparison with the list of C operators.

chk_prpop()

bool chk_prpop

(

const char *const

value

)

Checks if the given value is a preprocessor directive.

This function checks whether the provided string is a valid preprocessor directive in C/C++ code. Preprocessor directives are typically used to control the compilation process and are denoted by a # symbol followed by a keyword.

Parameters

value

A constant pointer to the string to be checked.

Returns

true if the value is a valid preprocessor directive, false otherwise.

Note

This function specifically checks for the presence of a # followed by a known preprocessor keyword. It does not verify the validity of the entire directive (such as checking if the syntax or arguments are correct).

chk_punct()

bool chk_punct

(

const char *const

value

)

Checks if the given value is a punctuation character.

This function checks if the provided string matches any of the predefined punctuation characters in C syntax. Punctuation characters include symbols like backslash, hash, dollar sign, parentheses, semicolon, etc., which serve various roles such as operators, delimiters, and special characters in the C language.

Parameters

value

A constant pointer to the string to be checked.

Returns

true if the value is one of the predefined punctuation characters, false otherwise.

Note

The function compares the given string against a set of predefined punctuation characters.

chk_sprtr()

bool chk_sprtr

(

const char

value

)

Checks if the given character is a valid separator.

This function checks if the provided character is one of the common separators in C syntax, such as parentheses, brackets, braces, or punctuation characters. It is used by the parser to identify and separate tokens based on these characters, which indicate boundaries between elements like function parameters, array elements, or preprocessor directives.

Parameters

value

A constant character to be checked.

Returns

true if the value is a separator (one of ()[]{}<>#$;,?:), false otherwise.

Note

The function checks for a single character and performs a direct comparison with a set of predefined separators.

chk_strlt()

bool chk_strlt

(

const char *const

value

)

Checks if the given value is a valid string literal.

This function checks whether the provided string represents a valid string literal in C/C++. A valid string literal is a sequence of characters enclosed in double quotes ("</tt>), including any escape sequences (e.g., <tt>\\"</tt>, <tt>\\\\</tt>). @param value A constant pointer to the string to be checked. @return <tt>true</tt> if the value is a valid string literal, <tt>false</tt> otherwise. @note A valid string literal must meet the following condition: - It starts and ends with double quotes (e.g., <tt>"hello"</tt> or <tt>"line
"), and it may contain escape sequences.