dynamiC  0.1

Dynamic type system for C with support for None, Boolean, Integer, Float, List, Sets, Dictionaries and others ...






$ git clone https://github.com/andre-dietrich/dynamiC


You can either generate a libdynC with make lib for dynamically linking or simply include this repository into your project and include it into your Makefile.

Basic data types

It is possible to define various basic data types as listed below:

#include "dynamic.h"
dyn_c var;
DYN_INIT(&var); // initialization with type NONE (undefined)
dyn_set_int(&var, 3);
dyn_set_float(&var, 3.14159);
dyn_set_string(&var, "PI");
dyn_set_extern(&var, void* anything ...);

List have to be initialized with a default buffer length, this buffer is automatically increased of decreased as the list grows or shrinks:

dyn_set_list_len(&list, 10);
dyn_length(&list); // results in 0
dyn_list_push(&list, &var);
dyn_list_push(&list, &var);
dyn_length(&list); // results in 2
// a placeholder to append elements of type NONE
dyn_length(&list); // results in 4
// to refer to an element use
dyn_list_get(&list, 1);
dyn_list_get(&list, 2);
// cleaning up
dyn_list_pop(&list, 2);

Any element can be coppied with the following function, previously allocated memory get cleaned up and new one gets created:

dyn_copy(&list, &var); // dyn_copy(from, to);
dyn_type(&var) == LIST; // otherwise NONE, BOOL, INTEGER, FLOAT, STRING, ...

Any type of dynamically allocated memory can be freed with one function, the resulting elements are reset to type NONE:


Complex structures

Further structures are sets and dictionaries, as for lists, memory is automatically increased or decreased:

dyn_c set;
dyn_set_set_len(&set, 1);
dyn_set_insert(&set, &var);
dyn_set_insert(&set, &var);
dyn_set_insert(&set, &var);
dyn_set_int(&var, -22);
dyn_set_insert(&set, &var);
dyn_set_insert(&set, &var);
dyn_set_insert(&set, &var);
dyn_length(&set); // results in 2
dyn_get_string(&set); // "{,-22}" first element of set is of type NONE
dyn_set_dict(&dict, 1);
dyn_dict_insert(&dict, &var, "key");
dyn_dict_insert(&dict, &var, "another key");
dyn_dict_insert(&dict, &set, "key3");
dyn_length(&dict); // results in 3
dyn_get_string(&dict); // "{'key': -22, 'another key': -22, 'key3': {,-22}}"
var = dyn_dict_get(&dict, "key"); // get reference
dyn_set_insert(&var, another dynamic element ...);


Operations are the commonly used +, -, *, /, <, ==,... bitshift ... among others. All of them are defined within dynamic_op.h with the naming convention dyn_op_operator with (operator == add, sub, le, eq, not, pow, ...). Their implementation mimics the common Python operators and the result of an operation is stored within the first function parameter, which gets rewritten:

dyn_c op1;
dyn_set_int(&op1, 2);
dyn_c op2;
dyn_set_int(&op1, 2);
dyn_op_add(&op1, &op2);
dyn_get_int(&op1); // returns 4
dyn_op_pow(&op1, &op2);
dyn_get_int(&op1); // returns 16

Depending on the used datatypes, different behavior is exposed for some operations, the highest datatype defines the result type, to which the other parameter is casted, see the enumeration in dynamic_types.h.

dyn_set_string(&op1, "string");
dyn_op_add(&op1, &op2); // results in "string2"

Furhtermore, and unlike in Python, the order of parameters results in different results:

dyn_op_add(&op2, &op1); // results in "2string2"
// or ...
dyn_op_add(&list, &element); // results in [ ..., element]
dyn_op_add(&element, &list); // results in [ element, ...]

Boolean operations can also be used for sets:

dyn_op_and(&set1, &set2); // union
dyn_op_or(&set1, &set2); // difference

Otherwise, and as in Python, dynamic elements are cast to boolean values:

dyn_get_bool(&none); // DYN_FALSE
dyn_get_bool(&integer); // DYN_FALSE if zero, otherwise DYN_TRUE
dyn_get_bool(&float__); // DYN_FALSE if zero, otherwise DYN_TRUE
dyn_get_bool(&string); // DYN_FALSE if empty, otherwise DYN_TRUE
dyn_get_bool(&list); // DYN_FALSE if empty, otherwise DYN_TRUE
dyn_get_bool(&set); // DYN_FALSE if empty, otherwise DYN_TRUE
dyn_get_bool(&dict); // DYN_FALSE if empty, otherwise DYN_TRUE
dyn_get_bool(&everythin_else); // DYN_FALSE

Boolean operations perform as usual, except if a value is NONE or associated with... Then a ternary operations gets applied

dyn_op_and(&true, &none); // NONE
dyn_op_and(&false, &none); // DYN_FALSE
dyn_op_or(&true, &none); // DYN_TRUE
dyn_op_or(&false, &none); // NONE
dyn_op_not(&none); // NONE

This behavior is quite usefull, if for example relational operations are applied onto dynamic elements, which cannot be compared, such as:

dyn_op_le(&string, &list); // NONE
dyn_op_gt(&procedure, &external); // NONE

The result element is of type NONE and can still be used in the further evaluation ...


This project is licensed under the MIT License - see the LICENSE.md file for details

Copyright (C) 2016-2017

André Dietrich dietr.nosp@m.ich@.nosp@m.ivs.c.nosp@m.s.un.nosp@m.i-mag.nosp@m.debu.nosp@m.rg.de