1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
|
# STC [ccommon](../include/stc/ccommon.h): Common definitions and handy macros
The following handy macros are safe to use, i.e. have no side-effects.
### c_auto, c_autovar, c_autoscope, c_autodefer
General ***defer*** mechanics for resource acquisition. These macros allows to specify the release of the
resource where the resource acquisition takes place. Makes it easier to verify that resources are released.
**NB**: These macros are one-time executed **for-loops**. Use ***only*** `c_exitauto` in order to break out
of these `c_auto*`-blocks! ***Do not*** use `return` or `goto` (or `break`) inside them, as they will
prevent the `end`-statement to be executed when leaving scope. This is not particular to the `c_auto*()`
macros, as one must always make sure to unwind temporary allocated resources before a `return` in C.
| Usage | Description |
|:---------------------------------------|:---------------------------------------------------|
| `c_auto (Type, var...)` | `c_autovar (Type var=Type_init(), Type_del(&var))` |
| `c_autovar (Type var=init, end...)` | Declare `var`. Defer `end...` to end of block |
| `c_autoscope (init, end...)` | Execute `init`. Defer `end...` to end of block |
| `c_autodefer (end...)` | Defer `end...` to end of block |
| `c_exitauto;` | Break safely out of a `c_auto*`-block/scope |
For multiple variables, use either multiple **c_autovar** in sequence, or declare variable outside
scope and use **c_autoscope**. Also, **c_auto** support up to 3 variables.
```c
c_autovar (cstr s = cstr_lit("Hello"), cstr_del(&s))
{
cstr_append(&s, " world");
printf("%s\n", s.str);
}
c_auto (cstr, s1, s2)
{
cstr_append(&s1, "Hello");
cstr_append(&s1, " world");
cstr_append(&s2, "Cool");
cstr_append(&s2, " stuff");
printf("%s %s\n", s1.str, s2.str);
}
MyData data;
c_autoscope (mydata_init(&data), mydata_destroy(&data))
{
printf("%s\n", mydata.name.str);
}
cstr s1 = cstr_lit("Hello"), s2 = cstr_lit("world");
c_autodefer (cstr_del(&s1), cstr_del(&s2))
{
printf("%s %s\n", s1.str, s2.str);
}
```
**Example**: Load each line of a text file into a vector of strings:
```c
#include <errno.h>
#include <stc/cstr.h>
#define i_val_str
#include <stc/cvec.h>
// receiver should check errno variable
cvec_str readFile(const char* name)
{
cvec_str vec = cvec_str_init(); // returned
c_autovar (FILE* fp = fopen(name, "r"), fclose(fp))
c_autovar (cstr line = cstr_null, cstr_del(&line))
while (cstr_getline(&line, fp))
cvec_str_emplace_back(&vec, line.str);
return vec;
}
int main()
{
c_autovar (cvec_str x = readFile(__FILE__), cvec_str_del(&x))
c_foreach (i, cvec_str, x)
printf("%s\n", i.ref->str);
}
```
### c_foreach
| Usage | Description |
|:-------------------------------------|:-----------------------------|
| `c_foreach (it, ctype, container)` | Iteratate all elements |
| `c_foreach (it, ctype, it1, it2)` | Iterate the range [it1, it2) |
```c
#define i_tag x
#define i_key int
#include <stc/csset.h>
...
c_apply(csset_x, insert, &set, {23, 3, 7, 5, 12});
c_foreach (i, csset_x, set)
printf(" %d", *i.ref);
// 3 5 7 12 23
csset_x_iter it = csset_x_find(&set, 7);
c_foreach (i, csset_x, it, csset_x_end(&set))
printf(" %d", *i.ref);
// 7 12 23
```
### c_forrange
Declare an iterator and specify a range to iterate with a for loop. Like python's ***for i in range()*** loop:
| Usage | Python equivalent |
|:----------------------------------------------|:-------------------------------------|
| `c_forrange (stop)` | `for _ in range(stop):` |
| `c_forrange (i, stop) // IterType = size_t` | `for i in range(stop):` |
| `c_forrange (i, IterType, stop)` | `for i in range(stop):` |
| `c_forrange (i, IterType, start, stop)` | `for i in range(start, stop):` |
| `c_forrange (i, IterType, start, stop, step)` | `for i in range(start, stop, step):` |
```c
c_forrange (5) printf("x");
// xxxxx
c_forrange (i, 5) printf(" %zu", i);
// 0 1 2 3 4
c_forrange (i, int, -3, 3) printf(" %d", i);
// -3 -2 -1 0 1 2
c_forrange (i, int, 30, 0, -5) printf(" %d", i);
// 30 25 20 15 10 5
```
### c_apply, c_apply_pair, c_apply_n
**c_apply** will apply a method on an existing container with the given array elements:
```c
c_apply(cvec_i, push_back, &vec, {1, 2, 3}); // apply multiple push_backs
c_apply_pair(cmap_i, insert, &map, { {4, 5}, {6, 7} }); // inserts to existing map
int arr[] = {1, 2, 3};
c_apply_n(cvec_i, push_back, &vec, arr, c_arraylen(arr));
```
### c_new, c_alloc, c_alloc_n, c_del, c_make
| Usage | Meaning |
|:-------------------------------|:----------------------------------------|
| `c_new (type, value)` | Move value to a new object on the heap |
| `c_alloc (type)` | `(type *) c_malloc(sizeof(type))` |
| `c_alloc_n (type, N)` | `(type *) c_malloc((N)*sizeof(type))` |
| `c_del (ctype, &c1, ..., &cN)` | `ctype_del(&c1); ... ctype_del(&cN)` |
| `c_make(type){value...}` | `(type){value...}` // c++ compatability |
```c
struct Pnt { double x, y, z; };
struct Pnt *pnt = c_new (struct Pnt, {1.2, 3.4, 5.6});
c_free(pnt);
int* array = c_alloc_n (int, 100);
c_free(array);
cstr a = cstr_from("Hello"), b = cstr_from("World");
c_del(cstr, &a, &b);
```
### c_malloc, c_calloc, c_realloc, c_free
Memory allocator for the entire library. Macros can be overloaded by the user.
### c_swap, c_arraylen
- **c_swap(type, x, y)**: Simple macro for swapping internals of two objects.
- **c_arraylen(array)**: Return number of elements in an array, e.g. `int array[] = {1, 2, 3, 4};`
|
