AST(3) Library Functions Manual AST(3)

# [NAME](#NAME)

expr - c-like expression library

# [SYNOPSIS](#SYNOPSIS)

```
#include <graphviz/expr.h>
Expr_t*          exopen(Exdisc_t*);
Excc_t*          exccopen(Expr_t*, Exccdisc_t*);
int              exccclose(Excc_t*);
void             exclose(Expr_t*, int);
char*            excontext(Expr_t*, char*, int);
void             exerror(const char*, ...);
Extype_t         exeval(Expr_t*, Exnode_t*, void*);
Exnode_t*        exexpr(Expr_t*, const char*, Exid_t*, int);
Exnode_t*        excast(Expr_t*, Exnode_t*, int, Exnode_t*, int);
Exnode_t*        exnewnode(Expr_t*, int, int, int, Exnode_t*, Exnode_t*);
void             exfreenode(Expr_t*, Exnode_t*);
int              expush(Expr_t*, const char*, int, const char*, FILE*);
int              expop(Expr_t*);
int              excomp(Expr_t*, const char*, int, const char*, FILE*);
int              extoken(Expr_t*);
char*            extype(long int);
Extype_t         exzero(long int);
```

# [DESCRIPTION](#DESCRIPTION)

exopen() is the first function called. exclose() is the last function called. exccopen() is the called if code generation will be used. exccclose() releases the state information allocated in exccopen().

# [SEE ALSO](#SEE_ALSO)

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Document: expr(3) from graphviz 16.1.0-r0 (Chainguard OS)
Source: https://gitlab.com/graphviz/graphviz