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Add tinyexpr library. Use tinyexpr for Quantity parsing.

tags/v2.0.0
Andrew Belt 5 years ago
parent
804dc4daf2
commit
213f51509c
4 changed files with 744 additions and 16 deletions
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  1. +1
    -0
      Makefile
  2. +86
    -0
      include/tinyexpr.h
  3. +4
    -16
      src/Quantity.cpp
  4. +653
    -0
      src/tinyexpr.c

+ 1
- 0
Makefile View File

@@ -14,6 +14,7 @@ SED := perl -pi -e
SOURCES += dep/nanovg/src/nanovg.c SOURCES += dep/nanovg/src/nanovg.c
SOURCES += dep/osdialog/osdialog.c SOURCES += dep/osdialog/osdialog.c
SOURCES += $(wildcard dep/jpommier-pffft-*/pffft.c) $(wildcard dep/jpommier-pffft-*/fftpack.c) SOURCES += $(wildcard dep/jpommier-pffft-*/pffft.c) $(wildcard dep/jpommier-pffft-*/fftpack.c)
SOURCES += $(wildcard src/*.c src/*/*.c)
SOURCES += $(wildcard src/*.cpp src/*/*.cpp) SOURCES += $(wildcard src/*.cpp src/*/*.cpp)


ifdef ARCH_LIN ifdef ARCH_LIN


+ 86
- 0
include/tinyexpr.h View File

@@ -0,0 +1,86 @@
/*
* TINYEXPR - Tiny recursive descent parser and evaluation engine in C
*
* Copyright (c) 2015-2018 Lewis Van Winkle
*
* http://CodePlea.com
*
* This software is provided 'as-is', without any express or implied
* warranty. In no event will the authors be held liable for any damages
* arising from the use of this software.
*
* Permission is granted to anyone to use this software for any purpose,
* including commercial applications, and to alter it and redistribute it
* freely, subject to the following restrictions:
*
* 1. The origin of this software must not be misrepresented; you must not
* claim that you wrote the original software. If you use this software
* in a product, an acknowledgement in the product documentation would be
* appreciated but is not required.
* 2. Altered source versions must be plainly marked as such, and must not be
* misrepresented as being the original software.
* 3. This notice may not be removed or altered from any source distribution.
*/

#ifndef __TINYEXPR_H__
#define __TINYEXPR_H__


#ifdef __cplusplus
extern "C" {
#endif



typedef struct te_expr {
int type;
union {double value; const double *bound; const void *function;};
void *parameters[1];
} te_expr;


enum {
TE_VARIABLE = 0,

TE_FUNCTION0 = 8, TE_FUNCTION1, TE_FUNCTION2, TE_FUNCTION3,
TE_FUNCTION4, TE_FUNCTION5, TE_FUNCTION6, TE_FUNCTION7,

TE_CLOSURE0 = 16, TE_CLOSURE1, TE_CLOSURE2, TE_CLOSURE3,
TE_CLOSURE4, TE_CLOSURE5, TE_CLOSURE6, TE_CLOSURE7,

TE_FLAG_PURE = 32
};

typedef struct te_variable {
const char *name;
const void *address;
int type;
void *context;
} te_variable;



/* Parses the input expression, evaluates it, and frees it. */
/* Returns NaN on error. */
double te_interp(const char *expression, int *error);

/* Parses the input expression and binds variables. */
/* Returns NULL on error. */
te_expr *te_compile(const char *expression, const te_variable *variables, int var_count, int *error);

/* Evaluates the expression. */
double te_eval(const te_expr *n);

/* Prints debugging information on the syntax tree. */
void te_print(const te_expr *n);

/* Frees the expression. */
/* This is safe to call on NULL pointers. */
void te_free(te_expr *n);


#ifdef __cplusplus
}
#endif

#endif /*__TINYEXPR_H__*/

+ 4
- 16
src/Quantity.cpp View File

@@ -1,5 +1,6 @@
#include <Quantity.hpp> #include <Quantity.hpp>
#include <string.hpp> #include <string.hpp>
#include <tinyexpr.h>




namespace rack { namespace rack {
@@ -14,23 +15,10 @@ std::string Quantity::getDisplayValueString() {
} }


void Quantity::setDisplayValueString(std::string s) { void Quantity::setDisplayValueString(std::string s) {
float v = 0.f;
char suffix[2];
int n = std::sscanf(s.c_str(), "%f%1s", &v, suffix);
if (n >= 2) {
// Parse SI prefixes
switch (suffix[0]) {
case 'n': v *= 1e-9f; break;
case 'u': v *= 1e-6f; break;
case 'm': v *= 1e-3f; break;
case 'k': v *= 1e3f; break;
case 'M': v *= 1e6f; break;
case 'G': v *= 1e9f; break;
default: break;
}
double result = te_interp(s.c_str(), NULL);
if (std::isfinite(result)) {
setDisplayValue(result);
} }
if (n >= 1)
setDisplayValue(v);
} }


std::string Quantity::getString() { std::string Quantity::getString() {


+ 653
- 0
src/tinyexpr.c View File

@@ -0,0 +1,653 @@
/*
* TINYEXPR - Tiny recursive descent parser and evaluation engine in C
*
* Copyright (c) 2015-2018 Lewis Van Winkle
*
* http://CodePlea.com
*
* This software is provided 'as-is', without any express or implied
* warranty. In no event will the authors be held liable for any damages
* arising from the use of this software.
*
* Permission is granted to anyone to use this software for any purpose,
* including commercial applications, and to alter it and redistribute it
* freely, subject to the following restrictions:
*
* 1. The origin of this software must not be misrepresented; you must not
* claim that you wrote the original software. If you use this software
* in a product, an acknowledgement in the product documentation would be
* appreciated but is not required.
* 2. Altered source versions must be plainly marked as such, and must not be
* misrepresented as being the original software.
* 3. This notice may not be removed or altered from any source distribution.
*/

/* COMPILE TIME OPTIONS */

/* Exponentiation associativity:
For a^b^c = (a^b)^c and -a^b = (-a)^b do nothing.
For a^b^c = a^(b^c) and -a^b = -(a^b) uncomment the next line.*/
/* #define TE_POW_FROM_RIGHT */

/* Logarithms
For log = base 10 log do nothing
For log = natural log uncomment the next line. */
/* #define TE_NAT_LOG */

#include "tinyexpr.h"
#include <stdlib.h>
#include <math.h>
#include <string.h>
#include <stdio.h>
#include <limits.h>

#ifndef NAN
#define NAN (0.0/0.0)
#endif

#ifndef INFINITY
#define INFINITY (1.0/0.0)
#endif


typedef double (*te_fun2)(double, double);

enum {
TOK_NULL = TE_CLOSURE7+1, TOK_ERROR, TOK_END, TOK_SEP,
TOK_OPEN, TOK_CLOSE, TOK_NUMBER, TOK_VARIABLE, TOK_INFIX
};


enum {TE_CONSTANT = 1};


typedef struct state {
const char *start;
const char *next;
int type;
union {double value; const double *bound; const void *function;};
void *context;

const te_variable *lookup;
int lookup_len;
} state;


#define TYPE_MASK(TYPE) ((TYPE)&0x0000001F)

#define IS_PURE(TYPE) (((TYPE) & TE_FLAG_PURE) != 0)
#define IS_FUNCTION(TYPE) (((TYPE) & TE_FUNCTION0) != 0)
#define IS_CLOSURE(TYPE) (((TYPE) & TE_CLOSURE0) != 0)
#define ARITY(TYPE) ( ((TYPE) & (TE_FUNCTION0 | TE_CLOSURE0)) ? ((TYPE) & 0x00000007) : 0 )
#define NEW_EXPR(type, ...) new_expr((type), (const te_expr*[]){__VA_ARGS__})

static te_expr *new_expr(const int type, const te_expr *parameters[]) {
const int arity = ARITY(type);
const int psize = sizeof(void*) * arity;
const int size = (sizeof(te_expr) - sizeof(void*)) + psize + (IS_CLOSURE(type) ? sizeof(void*) : 0);
te_expr *ret = malloc(size);
memset(ret, 0, size);
if (arity && parameters) {
memcpy(ret->parameters, parameters, psize);
}
ret->type = type;
ret->bound = 0;
return ret;
}


void te_free_parameters(te_expr *n) {
if (!n) return;
switch (TYPE_MASK(n->type)) {
case TE_FUNCTION7: case TE_CLOSURE7: te_free(n->parameters[6]); /* Falls through. */
case TE_FUNCTION6: case TE_CLOSURE6: te_free(n->parameters[5]); /* Falls through. */
case TE_FUNCTION5: case TE_CLOSURE5: te_free(n->parameters[4]); /* Falls through. */
case TE_FUNCTION4: case TE_CLOSURE4: te_free(n->parameters[3]); /* Falls through. */
case TE_FUNCTION3: case TE_CLOSURE3: te_free(n->parameters[2]); /* Falls through. */
case TE_FUNCTION2: case TE_CLOSURE2: te_free(n->parameters[1]); /* Falls through. */
case TE_FUNCTION1: case TE_CLOSURE1: te_free(n->parameters[0]);
}
}


void te_free(te_expr *n) {
if (!n) return;
te_free_parameters(n);
free(n);
}


static double pi(void) {return 3.14159265358979323846;}
static double e(void) {return 2.71828182845904523536;}
static double fac(double a) {/* simplest version of fac */
if (a < 0.0)
return NAN;
if (a > UINT_MAX)
return INFINITY;
unsigned int ua = (unsigned int)(a);
unsigned long int result = 1, i;
for (i = 1; i <= ua; i++) {
if (i > ULONG_MAX / result)
return INFINITY;
result *= i;
}
return (double)result;
}
static double ncr(double n, double r) {
if (n < 0.0 || r < 0.0 || n < r) return NAN;
if (n > UINT_MAX || r > UINT_MAX) return INFINITY;
unsigned long int un = (unsigned int)(n), ur = (unsigned int)(r), i;
unsigned long int result = 1;
if (ur > un / 2) ur = un - ur;
for (i = 1; i <= ur; i++) {
if (result > ULONG_MAX / (un - ur + i))
return INFINITY;
result *= un - ur + i;
result /= i;
}
return result;
}
static double npr(double n, double r) {return ncr(n, r) * fac(r);}

static const te_variable functions[] = {
/* must be in alphabetical order */
{"abs", fabs, TE_FUNCTION1 | TE_FLAG_PURE, 0},
{"acos", acos, TE_FUNCTION1 | TE_FLAG_PURE, 0},
{"asin", asin, TE_FUNCTION1 | TE_FLAG_PURE, 0},
{"atan", atan, TE_FUNCTION1 | TE_FLAG_PURE, 0},
{"atan2", atan2, TE_FUNCTION2 | TE_FLAG_PURE, 0},
{"ceil", ceil, TE_FUNCTION1 | TE_FLAG_PURE, 0},
{"cos", cos, TE_FUNCTION1 | TE_FLAG_PURE, 0},
{"cosh", cosh, TE_FUNCTION1 | TE_FLAG_PURE, 0},
{"e", e, TE_FUNCTION0 | TE_FLAG_PURE, 0},
{"exp", exp, TE_FUNCTION1 | TE_FLAG_PURE, 0},
{"fac", fac, TE_FUNCTION1 | TE_FLAG_PURE, 0},
{"floor", floor, TE_FUNCTION1 | TE_FLAG_PURE, 0},
{"ln", log, TE_FUNCTION1 | TE_FLAG_PURE, 0},
#ifdef TE_NAT_LOG
{"log", log, TE_FUNCTION1 | TE_FLAG_PURE, 0},
#else
{"log", log10, TE_FUNCTION1 | TE_FLAG_PURE, 0},
#endif
{"log10", log10, TE_FUNCTION1 | TE_FLAG_PURE, 0},
{"ncr", ncr, TE_FUNCTION2 | TE_FLAG_PURE, 0},
{"npr", npr, TE_FUNCTION2 | TE_FLAG_PURE, 0},
{"pi", pi, TE_FUNCTION0 | TE_FLAG_PURE, 0},
{"pow", pow, TE_FUNCTION2 | TE_FLAG_PURE, 0},
{"sin", sin, TE_FUNCTION1 | TE_FLAG_PURE, 0},
{"sinh", sinh, TE_FUNCTION1 | TE_FLAG_PURE, 0},
{"sqrt", sqrt, TE_FUNCTION1 | TE_FLAG_PURE, 0},
{"tan", tan, TE_FUNCTION1 | TE_FLAG_PURE, 0},
{"tanh", tanh, TE_FUNCTION1 | TE_FLAG_PURE, 0},
{0, 0, 0, 0}
};

static const te_variable *find_builtin(const char *name, int len) {
int imin = 0;
int imax = sizeof(functions) / sizeof(te_variable) - 2;

/*Binary search.*/
while (imax >= imin) {
const int i = (imin + ((imax-imin)/2));
int c = strncmp(name, functions[i].name, len);
if (!c) c = '\0' - functions[i].name[len];
if (c == 0) {
return functions + i;
} else if (c > 0) {
imin = i + 1;
} else {
imax = i - 1;
}
}

return 0;
}

static const te_variable *find_lookup(const state *s, const char *name, int len) {
int iters;
const te_variable *var;
if (!s->lookup) return 0;

for (var = s->lookup, iters = s->lookup_len; iters; ++var, --iters) {
if (strncmp(name, var->name, len) == 0 && var->name[len] == '\0') {
return var;
}
}
return 0;
}



static double add(double a, double b) {return a + b;}
static double sub(double a, double b) {return a - b;}
static double mul(double a, double b) {return a * b;}
static double divide(double a, double b) {return a / b;}
static double negate(double a) {return -a;}
static double comma(double a, double b) {(void)a; return b;}


void next_token(state *s) {
s->type = TOK_NULL;

do {

if (!*s->next){
s->type = TOK_END;
return;
}

/* Try reading a number. */
if ((s->next[0] >= '0' && s->next[0] <= '9') || s->next[0] == '.') {
s->value = strtod(s->next, (char**)&s->next);
s->type = TOK_NUMBER;
} else {
/* Look for a variable or builtin function call. */
if (s->next[0] >= 'a' && s->next[0] <= 'z') {
const char *start;
start = s->next;
while ((s->next[0] >= 'a' && s->next[0] <= 'z') || (s->next[0] >= '0' && s->next[0] <= '9') || (s->next[0] == '_')) s->next++;

const te_variable *var = find_lookup(s, start, s->next - start);
if (!var) var = find_builtin(start, s->next - start);

if (!var) {
s->type = TOK_ERROR;
} else {
switch(TYPE_MASK(var->type))
{
case TE_VARIABLE:
s->type = TOK_VARIABLE;
s->bound = var->address;
break;

case TE_CLOSURE0: case TE_CLOSURE1: case TE_CLOSURE2: case TE_CLOSURE3: /* Falls through. */
case TE_CLOSURE4: case TE_CLOSURE5: case TE_CLOSURE6: case TE_CLOSURE7: /* Falls through. */
s->context = var->context; /* Falls through. */

case TE_FUNCTION0: case TE_FUNCTION1: case TE_FUNCTION2: case TE_FUNCTION3: /* Falls through. */
case TE_FUNCTION4: case TE_FUNCTION5: case TE_FUNCTION6: case TE_FUNCTION7: /* Falls through. */
s->type = var->type;
s->function = var->address;
break;
}
}

} else {
/* Look for an operator or special character. */
switch (s->next++[0]) {
case '+': s->type = TOK_INFIX; s->function = add; break;
case '-': s->type = TOK_INFIX; s->function = sub; break;
case '*': s->type = TOK_INFIX; s->function = mul; break;
case '/': s->type = TOK_INFIX; s->function = divide; break;
case '^': s->type = TOK_INFIX; s->function = pow; break;
case '%': s->type = TOK_INFIX; s->function = fmod; break;
case '(': s->type = TOK_OPEN; break;
case ')': s->type = TOK_CLOSE; break;
case ',': s->type = TOK_SEP; break;
case ' ': case '\t': case '\n': case '\r': break;
default: s->type = TOK_ERROR; break;
}
}
}
} while (s->type == TOK_NULL);
}


static te_expr *list(state *s);
static te_expr *expr(state *s);
static te_expr *power(state *s);

static te_expr *base(state *s) {
/* <base> = <constant> | <variable> | <function-0> {"(" ")"} | <function-1> <power> | <function-X> "(" <expr> {"," <expr>} ")" | "(" <list> ")" */
te_expr *ret;
int arity;

switch (TYPE_MASK(s->type)) {
case TOK_NUMBER:
ret = new_expr(TE_CONSTANT, 0);
ret->value = s->value;
next_token(s);
break;

case TOK_VARIABLE:
ret = new_expr(TE_VARIABLE, 0);
ret->bound = s->bound;
next_token(s);
break;

case TE_FUNCTION0:
case TE_CLOSURE0:
ret = new_expr(s->type, 0);
ret->function = s->function;
if (IS_CLOSURE(s->type)) ret->parameters[0] = s->context;
next_token(s);
if (s->type == TOK_OPEN) {
next_token(s);
if (s->type != TOK_CLOSE) {
s->type = TOK_ERROR;
} else {
next_token(s);
}
}
break;

case TE_FUNCTION1:
case TE_CLOSURE1:
ret = new_expr(s->type, 0);
ret->function = s->function;
if (IS_CLOSURE(s->type)) ret->parameters[1] = s->context;
next_token(s);
ret->parameters[0] = power(s);
break;

case TE_FUNCTION2: case TE_FUNCTION3: case TE_FUNCTION4:
case TE_FUNCTION5: case TE_FUNCTION6: case TE_FUNCTION7:
case TE_CLOSURE2: case TE_CLOSURE3: case TE_CLOSURE4:
case TE_CLOSURE5: case TE_CLOSURE6: case TE_CLOSURE7:
arity = ARITY(s->type);

ret = new_expr(s->type, 0);
ret->function = s->function;
if (IS_CLOSURE(s->type)) ret->parameters[arity] = s->context;
next_token(s);

if (s->type != TOK_OPEN) {
s->type = TOK_ERROR;
} else {
int i;
for(i = 0; i < arity; i++) {
next_token(s);
ret->parameters[i] = expr(s);
if(s->type != TOK_SEP) {
break;
}
}
if(s->type != TOK_CLOSE || i != arity - 1) {
s->type = TOK_ERROR;
} else {
next_token(s);
}
}

break;

case TOK_OPEN:
next_token(s);
ret = list(s);
if (s->type != TOK_CLOSE) {
s->type = TOK_ERROR;
} else {
next_token(s);
}
break;

default:
ret = new_expr(0, 0);
s->type = TOK_ERROR;
ret->value = NAN;
break;
}

return ret;
}


static te_expr *power(state *s) {
/* <power> = {("-" | "+")} <base> */
int sign = 1;
while (s->type == TOK_INFIX && (s->function == add || s->function == sub)) {
if (s->function == sub) sign = -sign;
next_token(s);
}

te_expr *ret;

if (sign == 1) {
ret = base(s);
} else {
ret = NEW_EXPR(TE_FUNCTION1 | TE_FLAG_PURE, base(s));
ret->function = negate;
}

return ret;
}

#ifdef TE_POW_FROM_RIGHT
static te_expr *factor(state *s) {
/* <factor> = <power> {"^" <power>} */
te_expr *ret = power(s);

int neg = 0;
te_expr *insertion = 0;

if (ret->type == (TE_FUNCTION1 | TE_FLAG_PURE) && ret->function == negate) {
te_expr *se = ret->parameters[0];
free(ret);
ret = se;
neg = 1;
}

while (s->type == TOK_INFIX && (s->function == pow)) {
te_fun2 t = s->function;
next_token(s);

if (insertion) {
/* Make exponentiation go right-to-left. */
te_expr *insert = NEW_EXPR(TE_FUNCTION2 | TE_FLAG_PURE, insertion->parameters[1], power(s));
insert->function = t;
insertion->parameters[1] = insert;
insertion = insert;
} else {
ret = NEW_EXPR(TE_FUNCTION2 | TE_FLAG_PURE, ret, power(s));
ret->function = t;
insertion = ret;
}
}

if (neg) {
ret = NEW_EXPR(TE_FUNCTION1 | TE_FLAG_PURE, ret);
ret->function = negate;
}

return ret;
}
#else
static te_expr *factor(state *s) {
/* <factor> = <power> {"^" <power>} */
te_expr *ret = power(s);

while (s->type == TOK_INFIX && (s->function == pow)) {
te_fun2 t = s->function;
next_token(s);
ret = NEW_EXPR(TE_FUNCTION2 | TE_FLAG_PURE, ret, power(s));
ret->function = t;
}

return ret;
}
#endif



static te_expr *term(state *s) {
/* <term> = <factor> {("*" | "/" | "%") <factor>} */
te_expr *ret = factor(s);

while (s->type == TOK_INFIX && (s->function == mul || s->function == divide || s->function == fmod)) {
te_fun2 t = s->function;
next_token(s);
ret = NEW_EXPR(TE_FUNCTION2 | TE_FLAG_PURE, ret, factor(s));
ret->function = t;
}

return ret;
}


static te_expr *expr(state *s) {
/* <expr> = <term> {("+" | "-") <term>} */
te_expr *ret = term(s);

while (s->type == TOK_INFIX && (s->function == add || s->function == sub)) {
te_fun2 t = s->function;
next_token(s);
ret = NEW_EXPR(TE_FUNCTION2 | TE_FLAG_PURE, ret, term(s));
ret->function = t;
}

return ret;
}


static te_expr *list(state *s) {
/* <list> = <expr> {"," <expr>} */
te_expr *ret = expr(s);

while (s->type == TOK_SEP) {
next_token(s);
ret = NEW_EXPR(TE_FUNCTION2 | TE_FLAG_PURE, ret, expr(s));
ret->function = comma;
}

return ret;
}


#define TE_FUN(...) ((double(*)(__VA_ARGS__))n->function)
#define M(e) te_eval(n->parameters[e])


double te_eval(const te_expr *n) {
if (!n) return NAN;

switch(TYPE_MASK(n->type)) {
case TE_CONSTANT: return n->value;
case TE_VARIABLE: return *n->bound;

case TE_FUNCTION0: case TE_FUNCTION1: case TE_FUNCTION2: case TE_FUNCTION3:
case TE_FUNCTION4: case TE_FUNCTION5: case TE_FUNCTION6: case TE_FUNCTION7:
switch(ARITY(n->type)) {
case 0: return TE_FUN(void)();
case 1: return TE_FUN(double)(M(0));
case 2: return TE_FUN(double, double)(M(0), M(1));
case 3: return TE_FUN(double, double, double)(M(0), M(1), M(2));
case 4: return TE_FUN(double, double, double, double)(M(0), M(1), M(2), M(3));
case 5: return TE_FUN(double, double, double, double, double)(M(0), M(1), M(2), M(3), M(4));
case 6: return TE_FUN(double, double, double, double, double, double)(M(0), M(1), M(2), M(3), M(4), M(5));
case 7: return TE_FUN(double, double, double, double, double, double, double)(M(0), M(1), M(2), M(3), M(4), M(5), M(6));
default: return NAN;
}

case TE_CLOSURE0: case TE_CLOSURE1: case TE_CLOSURE2: case TE_CLOSURE3:
case TE_CLOSURE4: case TE_CLOSURE5: case TE_CLOSURE6: case TE_CLOSURE7:
switch(ARITY(n->type)) {
case 0: return TE_FUN(void*)(n->parameters[0]);
case 1: return TE_FUN(void*, double)(n->parameters[1], M(0));
case 2: return TE_FUN(void*, double, double)(n->parameters[2], M(0), M(1));
case 3: return TE_FUN(void*, double, double, double)(n->parameters[3], M(0), M(1), M(2));
case 4: return TE_FUN(void*, double, double, double, double)(n->parameters[4], M(0), M(1), M(2), M(3));
case 5: return TE_FUN(void*, double, double, double, double, double)(n->parameters[5], M(0), M(1), M(2), M(3), M(4));
case 6: return TE_FUN(void*, double, double, double, double, double, double)(n->parameters[6], M(0), M(1), M(2), M(3), M(4), M(5));
case 7: return TE_FUN(void*, double, double, double, double, double, double, double)(n->parameters[7], M(0), M(1), M(2), M(3), M(4), M(5), M(6));
default: return NAN;
}

default: return NAN;
}

}

#undef TE_FUN
#undef M

static void optimize(te_expr *n) {
/* Evaluates as much as possible. */
if (n->type == TE_CONSTANT) return;
if (n->type == TE_VARIABLE) return;

/* Only optimize out functions flagged as pure. */
if (IS_PURE(n->type)) {
const int arity = ARITY(n->type);
int known = 1;
int i;
for (i = 0; i < arity; ++i) {
optimize(n->parameters[i]);
if (((te_expr*)(n->parameters[i]))->type != TE_CONSTANT) {
known = 0;
}
}
if (known) {
const double value = te_eval(n);
te_free_parameters(n);
n->type = TE_CONSTANT;
n->value = value;
}
}
}


te_expr *te_compile(const char *expression, const te_variable *variables, int var_count, int *error) {
state s;
s.start = s.next = expression;
s.lookup = variables;
s.lookup_len = var_count;

next_token(&s);
te_expr *root = list(&s);

if (s.type != TOK_END) {
te_free(root);
if (error) {
*error = (s.next - s.start);
if (*error == 0) *error = 1;
}
return 0;
} else {
optimize(root);
if (error) *error = 0;
return root;
}
}


double te_interp(const char *expression, int *error) {
te_expr *n = te_compile(expression, 0, 0, error);
double ret;
if (n) {
ret = te_eval(n);
te_free(n);
} else {
ret = NAN;
}
return ret;
}

static void pn (const te_expr *n, int depth) {
int i, arity;
printf("%*s", depth, "");

switch(TYPE_MASK(n->type)) {
case TE_CONSTANT: printf("%f\n", n->value); break;
case TE_VARIABLE: printf("bound %p\n", n->bound); break;

case TE_FUNCTION0: case TE_FUNCTION1: case TE_FUNCTION2: case TE_FUNCTION3:
case TE_FUNCTION4: case TE_FUNCTION5: case TE_FUNCTION6: case TE_FUNCTION7:
case TE_CLOSURE0: case TE_CLOSURE1: case TE_CLOSURE2: case TE_CLOSURE3:
case TE_CLOSURE4: case TE_CLOSURE5: case TE_CLOSURE6: case TE_CLOSURE7:
arity = ARITY(n->type);
printf("f%d", arity);
for(i = 0; i < arity; i++) {
printf(" %p", n->parameters[i]);
}
printf("\n");
for(i = 0; i < arity; i++) {
pn(n->parameters[i], depth + 1);
}
break;
}
}


void te_print(const te_expr *n) {
pn(n, 0);
}

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