if_control Struct Reference

Maintains state with respect to #if logic. More...

#include <if_control.h>

Public Types
enum	if_state {   IF_STATE_OUTSIDE, IF_STATE_FALSE_PREFIX, IF_STATE_TRUE_PREFIX, IF_STATE_PASS_MIDDLE,   IF_STATE_FALSE_MIDDLE, IF_STATE_TRUE_MIDDLE, IF_STATE_PASS_ELSE, IF_STATE_FALSE_ELSE,   IF_STATE_TRUE_ELSE, IF_STATE_FALSE_TRAILER, IF_STATE_COUNT }
	symbolic constants denoting the if-control states. More...

Static Public Member Functions
static void	transition (line_type linetype)
	Transition the if-control state given an evaluated line type. More...
static bool	dead_line ()
	Is the current line rejected?
static bool	was_unconditional_line ()
	Is the current line outside any #if scope?
static bool	is_unconditional_line ()
	Is the current line outside any #if scope or in the scope of a satisfied #if?
static size_t	if_start_line ()
	Get the starting line number of the current #if sequence.
static size_t	if_depth ()
	Get the current depth of #if-nesting.
static if_state	state ()
	Get the current #if-state.
static void	top ()
	Reset the depth of #if-nesting to 0.

Private Types
using	transition_t ) = void(
	Type of #if-state transition functions.

Static Private Member Functions
static void	nest ()
	Increment the #if-nesting depth.
static void	set_state (if_state is)
	Set the #if-state at the current nesting depth.
static void	Strue ()
	State transition.
static void	Sfalse ()
	State transition.
static void	Selse ()
	State transition.
static void	Pelif ()
	State transition.
static void	Pelse ()
	State transition.
static void	Pendif ()
	State transition.
static void	Dfalse ()
	State transition.
static void	Delif ()
	State transition.
static void	Delse ()
	State transition.
static void	Dendif ()
	State transition.
static void	Fdrop ()
	State transition.
static void	Fpass ()
	State transition.
static void	Ftrue ()
	State transition.
static void	Ffalse ()
	State transition.
static void	Mpass ()
	State transition.
static void	Mtrue ()
	State transition.
static void	Melif ()
	State transition.
static void	Melse ()
	State transition.
static void	orphan_elif ()
	Diagnose an input orphan #elif on cerr
static void	orphan_else ()
	Diagnose an input orphan #else on cerr
static void	orphan_endif ()
	Diagnose an input orphan #endif on cerr
static void	early_eof ()
	Diagnose unexpected end of input on cerr

Static Private Attributes
static const unsigned	MAXDEPTH = 64
	Maximum depth of hash-if nesting. More...
static transition_t *const	transition_table [IF_STATE_COUNT][LT_SENTINEL]
	The #if-state transition table. More...
static if_state	ifstate [MAXDEPTH] = {if_state(0)}
	Array of states of nested #if-directives.
static size_t	depth = 0
	Current depth of #if-nesting.
static size_t	if_start_lines [MAXDEPTH] = {0}
	Array of start lines of nested #if-directives.

Detailed Description

Maintains state with respect to #if logic.

struct if_control maintains state with respect to #if logic in the course of parsing and provides queries on this state.

Definition at line 59 of file if_control.h.

Member Enumeration Documentation

enum if_control::if_state

symbolic constants denoting the if-control states.

Enumerator
IF_STATE_OUTSIDE	We are outside any if
IF_STATE_FALSE_PREFIX	We have a false if followed by false elif
IF_STATE_TRUE_PREFIX	The first non-false (el)if is true.
IF_STATE_PASS_MIDDLE	The first non-false (el)if is insoluble.
IF_STATE_FALSE_MIDDLE	We have a false elif after a pass state.
IF_STATE_TRUE_MIDDLE	We have a true elif after a pass state.
IF_STATE_PASS_ELSE	We have an else after a pass state.
IF_STATE_FALSE_ELSE	We have an else after a true state.
IF_STATE_TRUE_ELSE	We have an else after only false states.
IF_STATE_FALSE_TRAILER	All elifs after a true are false.
IF_STATE_COUNT	Count of if-control states.

Definition at line 62 of file if_control.h.

Member Function Documentation

void if_control::transition ( line_type  linetype )

static

Transition the if-control state given an evaluated line type.

The function advances a state-machine whose parameters are the current input linetype and the current if-control state. The transition performs the appropriate action to despatch the line just evaluated and sets a new if-state.

Parameters

linetype

The linetype of the last evaluated input line.

Definition at line 310 of file if_control.cpp.

Member Data Documentation

const unsigned if_control::MAXDEPTH = 64

staticprivate

Maximum depth of hash-if nesting.

c.f. Minimum translation limits from ISO/IEC 9899:1999 5.2.4.1

Definition at line 138 of file if_control.h.

if_control::transition_t *const if_control::transition_table

staticprivate

The #if-state transition table.

An array of pointers to state transition functions.

Definition at line 147 of file if_control.h.

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The documentation for this struct was generated from the following files:

• if_control.h
• if_control.cpp