Strings

Some simple string manipulation techniques are provided. Strings are arbitrarily long NULL-terminated character arrays, which are allocated and deleted as needed. The type STRING is defined as:

typedef  char   *STRING;

The basic string creation and deletion routines are:

public  STRING  alloc_string(
    int   length )
public  STRING  create_string(
    STRING    initial )

The function alloc_string allocates storage for a string of the desired length (by allocating length+1 bytes), without assigning any value to the string. The function create_string creates an allocated string with the value equal to initial. If initial is a NULL pointer an empty string (``'') is created.

public  void  delete_string(
    STRING   string )

The storage associated with a string may be deleted with this function.

public  int  string_length(
    STRING   string )

Returns the length of the string.

public  BOOLEAN  equal_strings(
    STRING   str1,
    STRING   str2 )

Returns TRUE if the two strings are exactly equal.

public  void  replace_string(
    STRING   *string,
    STRING   new_string )

A convenience function which deletes the string argument, and reassigns it to the new_string. It does not copy the value of new_string, but merely sets the string to the pointer new_string.

public  void  concat_char_to_string(
    STRING   *string,
    char     ch )

Concatenates a character to the end of the string.

public  STRING  concat_strings(
    STRING   str1,
    STRING   str2 )

Creates and returns a string which is the concatenation of the two arguments, without changing the string arguments.

public  void  concat_to_string(
    STRING   *string,
    STRING   str2 )

Replaces the argument string with the concatenation of the arguments string and str2.

public  BOOLEAN  is_lower_case(
    char  ch )

Returns TRUE if the character is a lower case letter.

public  BOOLEAN  is_upper_case(
    char  ch )

Returns TRUE if the character is a upper case letter.

public  char  get_lower_case(
    char   ch )

If the character is upper case, returns the lower case version of the character, otherwise, returns the character itself.

public  char  get_upper_case(
    char   ch )

If the character is lower case, returns the upper case version of the character, otherwise, returns the character itself.

public  BOOLEAN  string_ends_in(
    STRING   string,
    STRING   ending )

Determines if the string ends in the specified ending. For instance, passing the arguments, "rainfall" and "fall" returns TRUE.

public    STRING   strip_outer_blanks(
    STRING  str )

Returns a string which is the argument str without any leading or trailing blanks.

public  void  make_string_upper_case(
    STRING    string )

Converts the string to an all upper case string. Modifies the string in place.

public  int  find_character(
    STRING  string,
    char    ch )

Searches for the given character in the given string, returning the index where it was found, or -1 if it was not found.

public  BOOLEAN  blank_string(
    STRING   string )

Returns true if the string is empty or consists of only space, tab, and newline characters.