-/* Bison Action Scanner
+/* Bison Code Data Structure and Scanner.
Copyright (C) 2006 Free Software Foundation, Inc.
# define SCAN_CODE_H_
# include "location.h"
-# include "symlist.h"
-/* Keeps track of the maximum number of semantic values to the left of
- a handle (those referenced by $0, $-1, etc.) are required by the
- semantic actions of this grammar. */
+struct symbol_list;
+
+/**
+ * \brief
+ * Keeps track of the maximum number of semantic values to the left of a
+ * handle (those referenced by \c $0, \c $-1, etc.) that are required by the
+ * semantic actions of this grammar.
+ */
extern int max_left_semantic_context;
-void code_scanner_free (void);
+/**
+ * \brief
+ * A code passage captured from the grammar file and possibly translated,
+ * and/or properties associated with such a code passage.
+ * \note
+ * - Don't break encapsulation by accessing the fields directly. Use the
+ * provided interface functions.
+ */
+typedef struct code_props {
+ /**
+ * \brief
+ * What kind of \c code_props this is.
+ * \sa
+ * - \c code_props_none_init
+ * - \c code_props_plain_init
+ * - \c code_props_symbol_action_init
+ * - \c code_props_rule_action_init
+ */
+ enum {
+ CODE_PROPS_NONE, CODE_PROPS_PLAIN,
+ CODE_PROPS_SYMBOL_ACTION, CODE_PROPS_RULE_ACTION
+ } kind;
+
+ /**
+ * \brief
+ * The code passage contained within this \c code_props.
+ * \invariant
+ * - <tt>code_props::code = NULL</tt> iff
+ * <tt>code_props::kind = CODE_PROPS_NONE</tt>.
+ */
+ char const *code;
+ /**
+ * \brief
+ * The grammar file location of \c code_props::code.
+ * \invariant
+ * - \c code_props::location is undefined iff
+ * <tt>code_props::code = NULL</tt>.
+ */
+ location location;
+ /**
+ * \brief
+ * The value returned by \c code_props_is_value_used for this
+ * \c code_props.
+ */
+ bool is_value_used;
+
+ /**
+ * \brief
+ * The \c symbol_list node associated with this code passage.
+ * \invariant
+ * - <tt>code_props::rule != NULL</tt> iff \c code_props::kind is
+ * \c CODE_PROPS_RULE_ACTION.
+ */
+ struct symbol_list *rule;
+} code_props;
+
+/**
+ * \pre
+ * - <tt>self != NULL</tt>.
+ * \post
+ * - \c self has been overwritten to contain no code. (However, \c self may
+ * still be conceptually associated with some passage of code contained
+ * elsewhere. Thus, a call on <tt>code_props_is_value_used (*self)</tt>,
+ * for example, is still reasonable.)
+ */
+void code_props_none_init (code_props *self);
+
+/**
+ * \brief A \c code_props initializer equivalent to \c code_props_none_init.
+ */
+#define CODE_PROPS_NONE_INIT \
+ {CODE_PROPS_NONE, NULL, EMPTY_LOCATION_INIT, false, NULL}
+
+/**
+ * \brief
+ * A \c code_props initialized by \c CODE_PROPS_NONE_INIT with no further
+ * modification.
+ */
+extern code_props const code_props_none;
-/* The action of the rule R contains $$, $1 etc. referring to the values
- of the rule R. */
-char const *translate_rule_action (symbol_list *r);
+/**
+ * \pre
+ * - <tt>self != NULL</tt>.
+ * - <tt>code != NULL</tt>.
+ * - \c code is an untranslated code passage containing no Bison escapes.
+ * - \c code was extracted from the grammar file at \c code_loc.
+ * \post
+ * - \c self has been overwritten to represent the specified plain code
+ * passage.
+ * - \c self does not claim responsibility for the memory of \c code.
+ */
+void code_props_plain_init (code_props *self, char const *code,
+ location code_loc);
-/* The action A refers to $$ and @$ only, referring to a symbol. */
-char const *translate_symbol_action (char const *a, location l);
+/**
+ * \pre
+ * - <tt>self != NULL</tt>.
+ * - <tt>code != NULL</tt>.
+ * - \c code is an untranslated code passage. The only Bison escapes it
+ * might contain are \c $$ and \c \@$, referring to a single symbol.
+ * - \c code was extracted from the grammar file at \c code_loc.
+ * \post
+ * - \c self has been overwritten to represent the specified symbol action.
+ * - \c self does not claim responsibility for the memory of \c code.
+ */
+void code_props_symbol_action_init (code_props *self, char const *code,
+ location code_loc);
-/* The action contains no special escapes, just protect M4 special
- symbols. */
-char const *translate_code (char const *a, location l);
+/**
+ * \pre
+ * - <tt>self != NULL</tt>.
+ * - <tt>code != NULL</tt>.
+ * - <tt>rule != NULL</tt>.
+ * - \c code is the untranslated action of the rule for which \c rule is the
+ * LHS node. Thus, \c code possibly contains Bison escapes such as \c $$,
+ * \c $1, \c $2, etc referring to the values of the rule.
+ * \post
+ * - \c self has been overwritten to represent the specified rule action.
+ * - \c self does not claim responsibility for the memory of \c code or
+ * \c rule.
+ */
+void code_props_rule_action_init (code_props *self, char const *code,
+ location code_loc, struct symbol_list *rule);
+
+/**
+ * \pre
+ * - If there's a code passage contained in \c self and it contains Bison
+ * escapes, all grammar declarations have already been parsed as they may
+ * affect warnings and complaints issued here.
+ * \post
+ * - All M4 special symbols and Bison escapes have been translated in
+ * <tt>code_props_code_get (*self)</tt> iff
+ * <tt>code_props_code_get (*self \@pre) != NULL</tt>.
+ */
+void code_props_translate_code (code_props *self);
+
+/**
+ * \pre
+ * - None.
+ * \post
+ * - \c result = either:
+ * - The code passage contained with \c self.
+ * - \c NULL if none.
+ */
+char const *code_props_code_get (code_props const self);
+
+/**
+ * \pre
+ * - <tt>code_props_code_get (self) != NULL</tt>.
+ * \post
+ * - \c result = the grammar file location of
+ * <tt>code_props_code_get (self)</tt>.
+ */
+location code_props_location_get (code_props const self);
+
+/**
+ * \pre
+ * - \c self was not previously initialized with \c code_props_plain_init.
+ * \post
+ * - \c result = either:
+ * - \c false if either:
+ * - \c code_props_translate_code has never previously been invoked for
+ * the \c code_props that would contain the code passage associated
+ * with \c self. (If \c self is for a RHS \c symbol_list node, that
+ * \c code_props is not \c self. Instead, it's the \c code_props for
+ * the LHS symbol of the same rule.)
+ * - \c code_props_translate_code has been invoked for that
+ * \c code_props, but the symbol value associated with \c self was not
+ * referenced in the code passage.
+ * - \c true otherwise.
+ */
+bool code_props_is_value_used (code_props const self);
+
+/**
+ * \pre
+ * - None.
+ * \post
+ * - The dynamic memory allocated by the previous invocation of
+ * \c code_props_translate_code (if any) was freed. The \c code_props
+ * instance for which that \c code_props_translate_code was invoked is now
+ * invalid.
+ */
+void code_scanner_last_string_free (void);
+
+/**
+ * \pre
+ * - None.
+ * \post
+ * - All dynamic memory allocated during invocations of
+ * \c code_props_translate_code (if any) has been freed. All
+ * \c code_props instances and all pointers returned by
+ * \c code_props_code_get may now be invalid.
+ */
+void code_scanner_free (void);
#endif /* !SCAN_CODE_H_ */
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