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
|
from __future__ import annotations
from typing import TYPE_CHECKING
import dask.dataframe as dd
if TYPE_CHECKING:
from narwhals._dask.expr import DaskExpr
class DaskExprStringNamespace:
def __init__(self, expr: DaskExpr) -> None:
self._compliant_expr = expr
def len_chars(self) -> DaskExpr:
return self._compliant_expr._with_callable(lambda expr: expr.str.len(), "len")
def replace(self, pattern: str, value: str, *, literal: bool, n: int) -> DaskExpr:
return self._compliant_expr._with_callable(
lambda expr, pattern, value, literal, n: expr.str.replace(
pattern, value, regex=not literal, n=n
),
"replace",
pattern=pattern,
value=value,
literal=literal,
n=n,
)
def replace_all(self, pattern: str, value: str, *, literal: bool) -> DaskExpr:
return self._compliant_expr._with_callable(
lambda expr, pattern, value, literal: expr.str.replace(
pattern, value, n=-1, regex=not literal
),
"replace",
pattern=pattern,
value=value,
literal=literal,
)
def strip_chars(self, characters: str | None) -> DaskExpr:
return self._compliant_expr._with_callable(
lambda expr, characters: expr.str.strip(characters),
"strip",
characters=characters,
)
def starts_with(self, prefix: str) -> DaskExpr:
return self._compliant_expr._with_callable(
lambda expr, prefix: expr.str.startswith(prefix), "starts_with", prefix=prefix
)
def ends_with(self, suffix: str) -> DaskExpr:
return self._compliant_expr._with_callable(
lambda expr, suffix: expr.str.endswith(suffix), "ends_with", suffix=suffix
)
def contains(self, pattern: str, *, literal: bool) -> DaskExpr:
return self._compliant_expr._with_callable(
lambda expr, pattern, literal: expr.str.contains(
pat=pattern, regex=not literal
),
"contains",
pattern=pattern,
literal=literal,
)
def slice(self, offset: int, length: int | None) -> DaskExpr:
return self._compliant_expr._with_callable(
lambda expr, offset, length: expr.str.slice(
start=offset, stop=offset + length if length else None
),
"slice",
offset=offset,
length=length,
)
def split(self, by: str) -> DaskExpr:
return self._compliant_expr._with_callable(
lambda expr, by: expr.str.split(pat=by), "split", by=by
)
def to_datetime(self, format: str | None) -> DaskExpr:
return self._compliant_expr._with_callable(
lambda expr, format: dd.to_datetime(expr, format=format),
"to_datetime",
format=format,
)
def to_uppercase(self) -> DaskExpr:
return self._compliant_expr._with_callable(
lambda expr: expr.str.upper(), "to_uppercase"
)
def to_lowercase(self) -> DaskExpr:
return self._compliant_expr._with_callable(
lambda expr: expr.str.lower(), "to_lowercase"
)
|
