forked from KolibriOS/kolibrios
43795ab11a
(An improved version in conjunction with ktcc can generate executable files.) git-svn-id: svn://kolibrios.org@8733 a494cfbc-eb01-0410-851d-a64ba20cac60
177 lines
3.9 KiB
C
177 lines
3.9 KiB
C
/*
|
|
* Tiny BASIC
|
|
* Expression Handling Header
|
|
*
|
|
* Released as Public Domain by Damian Gareth Walker 2019
|
|
* Created: 16-Aug-2019
|
|
*/
|
|
|
|
|
|
#ifndef __EXPRESSION_H__
|
|
#define __EXPRESSION_H__
|
|
|
|
|
|
/* Forward Declarations */
|
|
typedef struct expression_node ExpressionNode;
|
|
typedef struct right_hand_term RightHandTerm;
|
|
typedef struct term_node TermNode;
|
|
typedef struct right_hand_factor RightHandFactor;
|
|
|
|
|
|
/*
|
|
* Data Definitions - Factors
|
|
*/
|
|
|
|
|
|
/* The different classes of factor */
|
|
typedef enum {
|
|
FACTOR_NONE, /* class as yet undetermined */
|
|
FACTOR_VARIABLE, /* a variable */
|
|
FACTOR_VALUE, /* an integer value */
|
|
FACTOR_EXPRESSION /* a bracketed expression */
|
|
} FactorClass;
|
|
|
|
/* The signs */
|
|
typedef enum {
|
|
SIGN_POSITIVE,
|
|
SIGN_NEGATIVE
|
|
} SignClass;
|
|
|
|
/* A factor */
|
|
typedef struct {
|
|
FactorClass class; /* what kind of factor is this? */
|
|
SignClass sign; /* which sign, positive or negative? */
|
|
union {
|
|
int variable;
|
|
int value;
|
|
ExpressionNode *expression;
|
|
} data;
|
|
} FactorNode;
|
|
|
|
|
|
/* The term operators */
|
|
typedef enum {
|
|
TERM_OPERATOR_NONE, /* single-factor term */
|
|
TERM_OPERATOR_MULTIPLY, /* multiply */
|
|
TERM_OPERATOR_DIVIDE /* divide */
|
|
} TermOperator;
|
|
|
|
/* the operator and right-hand part of a term */
|
|
typedef struct right_hand_factor {
|
|
TermOperator op; /* the operator to apply: muliply or divide */
|
|
FactorNode *factor; /* the factor to multiply or divide by */
|
|
RightHandFactor *next; /* the next part of the term, if any */
|
|
} RightHandFactor;
|
|
|
|
/* A term */
|
|
typedef struct term_node {
|
|
FactorNode *factor; /* the first factor of an expression */
|
|
RightHandFactor *next; /* the right side term, if any */
|
|
} TermNode;
|
|
|
|
/* Expression Operator */
|
|
typedef enum {
|
|
EXPRESSION_OPERATOR_NONE, /* single-term expression */
|
|
EXPRESSION_OPERATOR_PLUS, /* addition */
|
|
EXPRESSION_OPERATOR_MINUS /* substraction */
|
|
} ExpressionOperator;
|
|
|
|
/* the operator and right-hand part of an expression */
|
|
typedef struct right_hand_term {
|
|
ExpressionOperator op; /* the operator to apply: plus or minus */
|
|
TermNode *term; /* the term to add or subtract */
|
|
RightHandTerm *next; /* next part of the expression, if any */
|
|
} RightHandTerm;
|
|
|
|
/* An expression */
|
|
typedef struct expression_node {
|
|
TermNode *term; /* The first term of an expression */
|
|
RightHandTerm *next; /* the right side expression, if any */
|
|
} ExpressionNode;
|
|
|
|
|
|
/*
|
|
* Function Declarations
|
|
*/
|
|
|
|
|
|
/*
|
|
* Constructor for a factor
|
|
* returns:
|
|
* FactorNode* the new factor
|
|
*/
|
|
FactorNode *factor_create (void);
|
|
|
|
/*
|
|
* Destructor for a factor
|
|
* params:
|
|
* FactorNode* factor the doomed factor
|
|
*/
|
|
void factor_destroy (FactorNode *factor);
|
|
|
|
/*
|
|
* Constructor for a right-hand factor of a term
|
|
* returns:
|
|
* RightHandFactor* the new RH factor of a term
|
|
*/
|
|
RightHandFactor *rhfactor_create (void);
|
|
|
|
/*
|
|
* Recursive destructor for a right-hand factor of a term
|
|
* params:
|
|
* RightHandFactor* rhterm the doomed RH factor of a term
|
|
*/
|
|
void rhfactor_destroy (RightHandFactor *rhterm);
|
|
|
|
/*
|
|
* Constructor for a term
|
|
* returns:
|
|
* TermNode* the new term
|
|
*/
|
|
TermNode *term_create (void);
|
|
|
|
/*
|
|
* Destructor for a term
|
|
* params:
|
|
* TermNode* term the doomed term
|
|
*/
|
|
void term_destroy (TermNode *term);
|
|
|
|
/*
|
|
* Constructor for a right-hand expression
|
|
* returns:
|
|
* RightHandTerm* the RH term of an expression
|
|
*/
|
|
RightHandTerm *rhterm_create (void);
|
|
|
|
/*
|
|
* Recursive destructor for a right-hand term of an expression
|
|
* params:
|
|
* RightHandTerm* rhexpression the doomed RH expression
|
|
*/
|
|
void rhterm_destroy (RightHandTerm *rhterm);
|
|
|
|
/*
|
|
* Constructor for an expression
|
|
* returns:
|
|
* ExpressionNode* the new expression
|
|
*/
|
|
ExpressionNode *expression_create (void);
|
|
|
|
/*
|
|
* Destructor for a factor
|
|
* params:
|
|
* FactorNode* factor the doomed factor
|
|
*/
|
|
void factor_destroy (FactorNode *factor);
|
|
|
|
/*
|
|
* Destructor for a expression
|
|
* params:
|
|
* ExpressionNode* expression the doomed expression
|
|
*/
|
|
void expression_destroy (ExpressionNode *expression);
|
|
|
|
|
|
#endif
|