This topic describes the syntax, description, parameters, and return values of dictionary functions. This topic also provides examples of these functions.

set

Sets key-value pairs in a dictionary specified by the d parameter. The following table describes the details about this function.
Item Description
Syntax set(d, k, v)
Parameters
  • d: the name of the dictionary.
  • k: the key. Data type: any type.
  • v: the value. Data type: any type.
Examples
  • Example 1
    outer_keys=['e66fd4aa-f281-472f-b919-fc7e7474de25', '66fee78d-1887-42ec-9119-a9b50b7fbca2']
    say(concat('keys[1]=', get(outer_keys, 1)))
    say(concat('keys[2]=', get(outer_keys, 2)))
    
    inner_keys=[]
    set(inner_keys, 'dev', '243390eb-00b7-4551-a6b8-021bb34d1674')
    set(inner_keys, 'zeus', '4747d33b-12b0-45e6-ac10-a8e191d6adaa')
    
    def echo_each(k, v, u) {
        s = concat('keys[', k, ']=', v)
        say(s)
    }
    foreach(inner_keys, echo_each, [])                                                                                                                                             
  • Example 2
    d_inner = []
    set(d_inner, 'name', 'inner dsl')
    
    d_outer = []
    set(d_outer, 'dictA', d_inner)
    
    v = get(d_outer, 'dictA')
    if v {
        v = get(v, 'name')
        if v {
            add_rsp_header('X-DSL-NESTED-DICT', v)
        }
    }
Response parameters Returns a value of true. Response parameters of Example 1 and Example 2:
  • Example 1
    keys[1]=e66fd4aa-f281-472f-b919-fc7e7474de25
    keys[2]=66fee78d-1887-42ec-9119-a9b50b7fbca2
    keys[dev]=243390eb-00b7-4551-a6b8-021bb34d1674
    keys[zeus]=4747d33b-12b0-45e6-ac10-a8e191d6adaa
  • Example 2: A response header is added.
    X-DSL-NESTED-DICT: inner dsl

get

Retrieves the value (v) that corresponds to a key (k) from a dictionary (d). The following table describes the details about this function.
Item Description
Syntax get(d, k)
Parameters
  • d: the name of the dictionary.
  • k: the key. Data type: any type.
Examples
outer_keys=['e66fd4aa-f281-472f-b919-fc7e7474de25', '66fee78d-1887-42ec-9119-a9b50b7fbca2']
say(concat('keys[1]=', get(outer_keys, 1)))
say(concat('keys[2]=', get(outer_keys, 2)))

inner_keys=[]
set(inner_keys, 'dev', '243390eb-00b7-4551-a6b8-021bb34d1674')
set(inner_keys, 'zeus', '4747d33b-12b0-45e6-ac10-a8e191d6adaa')

def echo_each(k, v, u) {
    s = concat('keys[', k, ']=', v)
    say(s)
}
foreach(inner_keys, echo_each, [])                                                                                                                                             
Response parameters If the function succeeds, the value that corresponds to the specified key is returned. Otherwise, a value of false is returned. Response parameters of this example:
keys[1]=e66fd4aa-f281-472f-b919-fc7e7474de25
keys[2]=66fee78d-1887-42ec-9119-a9b50b7fbca2
keys[dev]=243390eb-00b7-4551-a6b8-021bb34d1674
keys[zeus]=4747d33b-12b0-45e6-ac10-a8e191d6adaa

foreach

Details about this function:
  • Traverses elements in a dictionary (d) and calls a callback function (f) for each element.
  • Specify the f parameter in the syntax of f(key, value, user_data).
  • When the f() function returns false, the foreach() loop ends.
The following table describes the details about this function:
Item Description
Syntax foreach(d, f, user_data)
Parameters
  • d: the name of the dictionary.
  • f: the callback function.
  • user_data: the user data that you want to transmit. Data type: dictionary.
Examples
  • Example 1
    outer_keys=['e66fd4aa-f281-472f-b919-fc7e7474de25', '66fee78d-1887-42ec-9119-a9b50b7fbca2']
    say(concat('keys[1]=', get(outer_keys, 1)))
    say(concat('keys[2]=', get(outer_keys, 2)))
    
    inner_keys=[]
    set(inner_keys, 'dev', '243390eb-00b7-4551-a6b8-021bb34d1674')
    set(inner_keys, 'zeus', '4747d33b-12b0-45e6-ac10-a8e191d6adaa')
    
    def echo_each(k, v, u) {
        s = concat('keys[', k, ']=', v)
        say(s)
    }
    foreach(inner_keys, echo_each, [])                                                                                                                                             
  • Example 2
    Prints the first two M3U8 slices and ends the foreach loop.
    def echo_each(k, v, u) {
        say(v)
    
        if match_re(v, '.*ts') {
            ts_cnt = get(u, 'ts_cnt')
            ts_cnt = add(ts_cnt, 1)
            set(u, 'ts_cnt', ts_cnt)
    
            if ge(ts_cnt, 2) {
                return false
            }
        }
    }
    
    m3u8 = ''
    m3u8 = concat(m3u8, '#EXTM3U8', '\n')
    m3u8 = concat(m3u8, '#EXT-X-MEDIA-SEQUENCE:140651513\n')
    m3u8 = concat(m3u8, '#EXT-X-TARGETDURATION:10\n')
    m3u8 = concat(m3u8, '#EXTINF:8,\n')
    m3u8 = concat(m3u8, 'http://vapp1.fw.live.cntv.cn/cache/289_/seg0/index140651514_140651513.ts\n')
    m3u8 = concat(m3u8, '#EXTINF:9,\n')
    m3u8 = concat(m3u8, 'http://vapp1.fw.live.cntv.cn/cache/289_/seg0/index140651514_140651514.ts\n')
    m3u8 = concat(m3u8, '#EXTINF:10,\n')
    m3u8 = concat(m3u8, 'http://vapp1.fw.live.cntv.cn/cache/289_/seg0/index140651514_140651515.ts\n')
    
    lines = split(m3u8, '\n')
    u = []
    set(u, 'ts_cnt', 0)
    foreach(lines, echo_each, u)
Response parameters Returns a value of true. Response parameters of Example 1 and Example 2:
  • Example 1
    keys[1]=e66fd4aa-f281-472f-b919-fc7e7474de25
    keys[2]=66fee78d-1887-42ec-9119-a9b50b7fbca2
    keys[dev]=243390eb-00b7-4551-a6b8-021bb34d1674
    keys[zeus]=4747d33b-12b0-45e6-ac10-a8e191d6adaa
  • Example 2
    #EXTM3U8
    #EXT-X-MEDIA-SEQUENCE:140651513
    #EXT-X-TARGETDURATION:10
    #EXTINF:8,
    http://vapp1.fw.live.cntv.cn/cache/289_/seg0/index140651514_140651513.ts
    #EXTINF:9,
    http://vapp1.fw.live.cntv.cn/cache/289_/seg0/index140651514_140651514.ts

del

Deletes key-value pairs from a dictionary (d). The following tables describes the details about this function.
Item Description
Syntax del(d, k)
Parameters
  • d: the name of the dictionary.
  • k: the key. Data type: any type.
Examples
var_a = []
set(var_a, 'note_a', 'note a info')
if get(var_a, 'note_a') {
    add_rsp_header('X-RESPOND-OUTPUT', 'found var_a key', true)
} else {
    add_rsp_header('X-RESPOND-OUTPUT', 'del var_a key', true)
}
del(var_a, 'note_a')
if get(var_a, 'note_a') {
    add_rsp_header('X-RESPOND-OUTPUT', 'found var_a key', true)
} else {
    add_rsp_header('X-RESPOND-OUTPUT', 'del var_a key', true)
}
Response parameters Returns a value of true. Response parameter for this example:
X-RESPOND-OUTPUT: found var_a key
X-RESPOND-OUTPUT: del var_a key

insert

Inserts elements into a dictionary. The following table describes the details about this function.
Item Description
Syntax insert(list, value, [,pos])
Parameter
  • list: the dictionary into which you want to insert elements.
  • value: the element that you want to insert. The value supports all data types.
  • pos: a numeric value. By default, the index of the dictionary specified by the list parameter starts from 1. The index cannot be 0. The element specified by the value parameter is inserted into the position specified by the pos parameter. Elements that follow the inserted element are moved towards the end of the dictionary for one position. If you do not specify the pos parameter, the element is inserted into the end of the dictionary.
Example
tbl_1 = []
insert(tbl_1, '1')
insert(tbl_1, '3')
insert(tbl_1, '5')
insert(tbl_1, '2')
insert(tbl_1, '6', 1)
str = tbl_concat(tbl_1, '')
say(concat('insert:', str))
Return value This function always returns a value of true. Return value in this example:
insert:61352 

sort

Sorts elements in a dictionary in the default order. The following table describes the details about this function.
Item Description
Syntax sort(list[, comp])
Feature If you specify the comp parameter, it must be a function that supports two elements in the specified dictionary as its parameters. A value of true is returned if the first element is placed before the second element. Therefore, a value of true is returned after the elements in the not comp(a, b) function are sorted. If you do not specify the comp parameter, the elements are sorted based on ANSII codes in ascending order. However, this sorting algorithm is unstable and may change the original order of two elements that have the same rank in the ANSII table.
Parameter
  • list: the dictionary whose elements you want to sort.
  • comp: the custom sorting algorithm, which must be a function.
Example
tbl_1 = []
insert(tbl_1, '1')
insert(tbl_1, '3')
insert(tbl_1, '5')
insert(tbl_1, '2')
say(concat('remove:', remove(tbl_1, 2)))
str = tbl_concat(tbl_1, '')
say(concat('insert:', str))
sort(tbl_1)
str = tbl_concat(tbl_1, '')
say(concat('sort:', str))
def my_comp(a, b){
  a = tonumber(a)
  b = tonumber(b)
  if gt(a, b) {
    return true
  }
  return false
}
sort(tbl_1, my_comp)
str = tbl_concat(tbl_1, '')
say(concat('sort_comp:', str))
Return value This function always returns a value of true. Return values in this example:
remove:3
insert:152
sort:1235
sort_comp:521 

remove

Removes the element from the specified position in a dictionary and returns the removed element. If you do not specify the pos parameter, the element that is at the end of the dictionary is removed. The following table describes the details about this function.
Item Description
Syntax remove(list, [, pos])
Parameter
  • list: the dictionary from which you want to remove elements.
  • pos: a numeric value.
Example
tbl_1 = []
insert(tbl_1, '1')
insert(tbl_1, '3')
insert(tbl_1, '5')
insert(tbl_1, '2')
say(concat('remove:', remove(tbl_1, 2)))
Return value Returns the element that is removed from the specified position. Return value in this example:
remove:3