PLVprs: String Parsing

The PLVprs (PL/Vision PaRSe) package offers a set of programs which provide generic and flexible string parsing capabilities. See PLVprs, PLVtkn, and PLVprsps: Parsing Strings for details.

Package constants

• c_ignore_case CONSTANT VARCHAR2(1) := 'I';
• c_respect_case CONSTANT VARCHAR2(1) := 'R';
• Use these constants to indicate whether you want case to be ignored or respected in the current operation.
• c_all CONSTANT VARCHAR(3) := 'ALL';
• c_word CONSTANT VARCHAR(4) := 'WORD';
• c_delim CONSTANT VARCHAR(5) := 'DELIM';
• The different types of atomics; c_all indicates "all atomics"; c_word indicates "words only"; c_delim indicates "delimiters only".
• std_delimiters CONSTANT VARCHAR2 (50) :=
• '!@#$%^&*()-_=+\|`~{{]}; :''",<.>/?' ||
• PLVchr.newline_char || PLVchr.tab_char || PLVchr.space_char;
• The standard set of delimiter characters.
• plsql_delimiters CONSTANT VARCHAR2 (50) :=
• '!@%^&*()-=+\|`~{{]}; :''",<.>/?' ||
• PLVchr.newline_char || PLVchr.tab_char || PLVchr.space_char;
• The set of delimiters for the PL/SQL language; this list is a bit different from the std_delimiters. The underscore and pound sign characters, for example, are not delimiters in PL/SQL.

5.21.2 Wrapping long strings into paragraphs

• PROCEDURE wrap
• (text_in IN VARCHAR2,
• line_length IN INTEGER,
• paragraph_out IN OUT PLVtab.vc2000_table,
• num_lines_out IN OUT INTEGER);
• Wraps the string provided by text_in into separate lines with a maximum specified length, each line of which is stored in consecutive rows in a PL/SQL table.
• FUNCTION wrapped_string
• (text_in IN VARCHAR2,
• line_length IN INTEGER := 80,
• prefix_in IN VARCHAR2 := NULL)
• RETURN VARCHAR2;
• Returns a long string wrapped into a series of lines separated by newline characters. This version of wrap avoids the need to define and manipulate a PL/SQL table.
• PROCEDURE display_wrap
• (text_in IN VARCHAR2,
• line_length IN INTEGER := 80,
• prefix_in IN VARCHAR2 := NULL);
• Displays the wrapped version of text_in using the p.l procedure (and DBMS_OUTPUT.PUT_LINE).

Analyzing string contents

• FUNCTION next_atom_loc
• (string_in IN VARCHAR2,
• start_loc_in IN NUMBER,
• direction_in IN NUMBER := +1,
• delimiters_in IN VARCHAR2 := std_delimiters)
• RETURN INTEGER;
• Returns the location in the string of the next atomic. You provide the starting location of the scan, the direction of the scan (usually +1 or -1, but you can provide other values as well), and the delimiters to be used in the scan.
• FUNCTION numatomics
• (string_in IN VARCHAR2,
• count_type_in IN VARCHAR2 := c_all,
• delimiters_in IN VARCHAR2 := std_delimiters)
• RETURN INTEGER;
• Returns the number of atomics in a string, where the definition of an atomic is provided by the count type (all or word or delimiter) and the set of delimiters.
• FUNCTION nth_atomic
• (string_in IN VARCHAR2,
• nth_in IN NUMBER,
• count_type_in IN VARCHAR2 := c_all,
• delimiters_in IN VARCHAR2 := std_delimiters)
• RETURN VARCHAR2;
• Returns the nth atomic in a string, where the definition of an atomic is provided by the count type (all or word or delimiter) and the set of delimiters.
• FUNCTION numinstr
• (string_in IN VARCHAR2,
• substring_in IN VARCHAR2,
• ignore_case_in IN VARCHAR2 := c_ignore_case)
• RETURN INTEGER;
• Returns the number of times a substring occurs in a string. You can choose to perform a search that is case-sensitive or that ignores case.

Parsing strings

• PROCEDURE string
• (string_in IN VARCHAR2,
• atomics_list_out OUT PLVtab.vc2000_table,
• num_atomics_out IN OUT NUMBER,
• delimiters_in IN VARCHAR2 := std_delimiters);
• Parses a string into atomics that are loaded into a PL/SQL table. You decide which characters will serve as the delimiters.
• PROCEDURE string
• (string_in IN VARCHAR2,
• atomics_list_out IN OUT VARCHAR2,
• num_atomics_out IN OUT NUMBER,
• delimiters_in IN VARCHAR2 := std_delimiters);
• Parses a string into atomics stored in a string with each atomic separated by a vertical bar. Once again, you decide which characters will serve as the delimiters.
• PROCEDURE display_atomics
• (string_in IN VARCHAR2,
• delimiters_in IN VARCHAR2 := std_delimiters);
• Displays the individual atomics in a string, as defined by the provided list of delimiters.