builtin
KCL provides a list of built-in functions that are automatically loaded and can be used directly without providing any module name. For example, print is a function provided by a widely used built-in module.
Type Conversion Functions
KCL's bool, int, float, str, list, dict and other types have built-in conversion functions of the same name. Among them, int can not only be used to truncate floating-point numbers, but also can be used to convert strings to integers (decimal when parsing, other values can also be specified).
The following are common uses of type-related functions:
b1 = bool(1) # true
b2 = bool(1.5) # true
b3 = bool("true") # true
b4 = bool("") # false
b5 = bool([]) # false
b6 = bool({}) # false
i1 = int("11") # 11
i2 = int("11", base=8) # 9
i3 = int("11", base=2) # 3
f1 = float(1) # 1.0
f2 = float("1.5") # 1.5
s1 = str(1) # 1
l1 = list([1, 2, 3])
String Builtin Member Functions
print
print(*args:any, end:str='\n')
The built-in print function, which provides different types of variable parameter printing, adds a newline at the end by default. The following are common usages:
print("hello KCL")
print()
print(None, end=':')
print(None)
print(True)
print(False)
print(123)
print(123.0)
print('abc ${123}')
print("abc ${456}")
print([1,'a', True])
print(1,'a', True)
print({})
print({a: 123})
The output is:
hello KCL
None:None
True
False
123
123.0
abc 123
abc 456
[1, 'a', True]
1 a True
{}
{'a': 123}
If you do not want the default newline, you can re-specify the ending string with the end='' named parameter.
print("Hello KCL", end='')
multiplyof
multiplyof(a:int, b:int) -> bool
Check whether the integer a is an integer multiple of b, and return a boolean value:
print(multiplyof(2, 1)) # True
print(multiplyof(1, 2)) # False
print(multiplyof(0, 1)) # True
print(multiplyof(0, 2)) # True
print(multiplyof(1, 0)) # Error
0 is a multiple of any number. But b cannot be 0, otherwise an exception will be thrown.
isunique
isunique(list: [any]) -> bool
Check if there are duplicate elements in an array, and return a boolean value:
print(isunique([])) # True
print(isunique([1])) # True
print(isunique([1, 2])) # True
print(isunique([1, 1])) # False
print(isunique([1, 1.0])) # False
print(isunique([1.1, 1.1])) # False
print(isunique(['abc', "abc"])) # False
print(isunique(['abc', "a${'bc'}"])) # False
It should be noted that integers and floating-point numbers ignore the type difference and judge whether the values are equal.
len
len(x: str | [any] | {:}) -> int
Return the length of strings, lists, and arrays:
print(len([])) # 0
print(len({})) # 0
print(len([1])) # 1
print(len({abc:123})) # 1
print("abc") # 3
Note: Calculating lengths on schema objects is not supported.
abs
abs(x: number) -> number
Calculate the absolute value of x.
all_true
all_true(x:str|[]|{:}) -> bool
Judging that all elements of a list or dictionary class are true, the usage is as follows:
print(all_true([])) # True
print(all_true({})) # True
print(all_true([True])) # True
print(all_true([1])) # True
print(all_true([True, False])) # False
print(all_true([True, None])) # False
Returns true when the list is empty.
any_true
any_true(x:str|[]|{:}) -> bool
Judging that at least one element in the iterable object is true, the usage is as follows:
print(any_true([])) # False
print(any_true([1])) # True
bin
bin(x:number) -> str
A string that returns the binary representation of an integer, used as follows:
print(bin(8)) # 0b1000
hex
hex(number)
A string that returns the hexadecimal representation of an integer, used as follows:
print(hex(18)) # 0x12
oct
oct(number)
A string that returns the octal representation of an integer, used as follows:
print(oct(10)) # 0o12
option
option(key:str, type:str='', required=False, default=None, help="") -> any
Gets the value of the command line top level argument input.
ord
ord(c) -> int
Get the Unicode code point value of the character, the usage is as follows:
print(ord('A')) # 65
print(ord('B')) # 66
print(ord('C')) # 67
sorted
sorted(x: []) -> []
Returns the sorted list, used as follows:
_a = []
_b = [2, 1]
_c = sorted(_a)
_d = sorted(_b)
print(_a) # []
print(_b) # [2, 1]
print(_c) # []
print(_d) # [1, 2]
range
range(start:int, end:int, step=1) -> [int]
Generates an iterable list, used as follows:
print(range(1,5)) # [1, 2, 3, 4]
print(range(1,5, 2)) # [1, 3]
print(range(5, 1, -1)) # [5, 4, 3, 2]
min
min(x:[number]) -> number
Returns the smallest element in the list, used as follows:
print(min([1,2])) # 1
print(min([2,1])) # 1
max
max(x:[number]) -> number
Returns the largest element in the list, used as follows:
print(max([1,2])) # 2
print(max([2,1])) # 2
sum
sum(x:[number], init_value=0) -> number
Returns the sum of all elements in the list, used as follows:
print(sum([1,2])) # 3
print(sum([2,1], 1000)) # 1003
pow
pow(x: number, y: number, z: number = None) -> number
Computes x**y, or (x**y)%z if z is not empty, supports integer and floating point numbers, used as follows:
print(pow(2,3)) # 8
print(pow(2, 3, 5)) # 8%5 == 3
print(pow(2, 0.5)) # 1.414
round
round(number: int|float, ndigits:int|None) -> float | int
Returns the rounded approximation of number. If ndigits is not None returns a float with the specified number of decimal places (cannot be negative), otherwise returns an integer structure, used as follows:
print(round(1)) # 1
print(round(1.4)) # 1
print(round(1.5)) # 2
print(round(1.5555, 1)) # 1.6
print(round(1.5555, 2)) # 1.56
print(round(1.5555)) # 2
print(round(1.5555, 0)) # 2.0
It should be noted that the difference between ndigits being None and 0 is that the prefix returns int type, the latter returns float type.
typeof
typeof(x: any, full_name: bool = False) -> str
Output the type of x at runtime. When the full_name parameter is set to True, the package prefix of the form pkg.schema will be returned, used as follows:
import sub as pkg
_a = 1
t1 = typeof(_a)
t2 = typeof("abc")
schema Person:
name?: any
_x1 = Person{}
t3 = typeof(_x1)
_x2 = pkg.Person{}
t4 = typeof(_x2)
t5 = typeof(_x2, full_name=True)
t6 = typeof(_x1, full_name=True)
# Output
# t1: int
# t2: str
# t3: Person
# t4: Person
# t5: sub.Person
# t6: __main__.Person
zip
zip(*args: str|list|dict)
It is used to take an iterable object as a parameter, pack the corresponding elements in the object into tuples, and then return a list composed of these tuples, used as follows:
a = zip([0, 1, 2], [3, 4, 5])
b = zip([0, 1], [3, 4, 5])
c = zip([0, 1, 2], [3, 4, 5, 6])
# Output
# a:
# - - 0
# - 3
# - - 1
# - 4
# - - 2
# - 5
# b:
# - - 0
# - 3
# - - 1
# - 4
# c:
# - - 0
# - 3
# - - 1
# - 4
# - - 2