[Chapter 5] 5.16 PLVlex: Lexical Analysis

5.16 PLVlex: Lexical Analysis

The PLVlex (PL/Vision LEXical analysis) package provides generic string-parsing extensions to PL/SQL ; these extensions include an awareness of the syntax and delimiters of the PL/SQL language. See the companion disk for details.

5.16.1 Analyzing PL/SQL string content

FUNCTION is_delimiter
(character_in IN VARCHAR2, exclude_in IN VARCHAR2 := NULL)
RETURN BOOLEAN;: Returns TRUE if the string is a PL/SQL delimiter.
FUNCTION is_oneline_comment (token_in IN VARCHAR2) RETURN BOOLEAN;: Returns TRUE if the string is a single-line comment indicator (a double hyphen).
FUNCTION starts_multiline_comment (token_in IN VARCHAR2)
RETURN BOOLEAN;: Returns TRUE if the string is equal to /* , which signals the start of a multiline or block comment.
FUNCTION ends_multiline_comment (token_in IN VARCHAR2)
RETURN BOOLEAN;: Returns TRUE if the string is equal to */ , which signals the end of a multiline or block comment.

5.16.2 Scanning PL/SQL strings

FUNCTION next_atom_loc
(string_in IN VARCHAR2, start_loc_in IN NUMBER)
RETURN NUMBER;: Returns the location of the beginning of the next PL/SQL atomic in the string.
PROCEDURE get_next_atomic
(line_in IN VARCHAR2,
start_pos_in IN VARCHAR2,
atomic_out OUT VARCHAR2,
new_start_pos_out OUT INTEGER,
line_len_in IN INTEGER := NULL);: Gets the next PL/SQL atomic from the string. This procedure builds upon PLVlex.next_atom_loc and several low-level PLVprs functions to scan the string from the perspective of a line of PL/SQL source code.
PROCEDURE get_next_token
(line_in IN VARCHAR2,
start_pos_in IN VARCHAR2,
token_out IN OUT VARCHAR2,
new_start_pos_out IN OUT INTEGER,
skip_spaces_in IN BOOLEAN,
line_len_in IN INTEGER := NULL,
full_qualified_name_in IN BOOLEAN := FALSE);: Gets the next PL/SQL token (which could be composed of multiple atomics) from the string.