Merge pull request #170 from tushushu/wip-read-csv-utils

A half done `read_csv` func

Author: tushushu

ulist/python/ulist/__init__.py

@@ -1,6 +1,7 @@
 from .constructor import arange, cycle, from_seq, repeat  # noqa:F401
 from .control_flow import select  # noqa:F401
 from .core import UltraFastList  # noqa:F401
+from .io import read_csv  # noqa:F401
 from .ulist import IndexList  # noqa:F401
 
 __version__ = "0.10.0"

ulist/python/ulist/io.py

@@ -0,0 +1,11 @@
+from __future__ import annotations  # To avoid circular import.
+from .ulist import read_csv as _read_csv
+from typing import List, TYPE_CHECKING
+
+if TYPE_CHECKING:  # To avoid circular import.
+    from . import UltraFastList
+
+
+def read_csv() -> List[UltraFastList]:
+    from . import UltraFastList  # To avoid circular import.
+    return [UltraFastList(x) for x in _read_csv()]

ulist/python/ulist/ulist.pyi

@@ -293,6 +293,9 @@ def arange32(start: int, stop: int, step: int) -> IntegerList32: ...
 def arange64(start: int, stop: int, step: int) -> IntegerList64: ...
 
 
+def read_csv() -> list: ...
+
+
 def select_bool(
     conditions: List[BooleanList],
     choices: LIST_PY,

ulist/src/io.rs

@@ -0,0 +1,27 @@
+use crate::boolean::BooleanList;
+use crate::floatings::FloatList64;
+use crate::integers::IntegerList64;
+use crate::string::StringList;
+use pyo3::prelude::*;
+use std::collections::HashSet;
+use std::iter::FromIterator;
+
+#[pyfunction]
+pub fn read_csv(py: Python) -> Vec<PyObject> {
+    // This is an example implementation of `read_csv` function, which will return
+    // PyList[BooleanList[True, False, None], IntegerList64[2, 3, None],
+    // FloatList64[2.0, 3.0, None], StringList['foo', 'bar', None]]
+    let blist = BooleanList::new(vec![true, false, false], HashSet::from_iter(vec![2]));
+    let ilist = IntegerList64::new(vec![2, 3, 0], HashSet::from_iter(vec![2]));
+    let flist = FloatList64::new(vec![2.0, 3.0, 0.0], HashSet::from_iter(vec![2]));
+    let slist = StringList::new(
+        vec!["foo".to_string(), "bar".to_string(), "".to_string()],
+        HashSet::from_iter(vec![2]),
+    );
+    let mut result: Vec<PyObject> = Vec::new();
+    result.push(blist.into_py(py));
+    result.push(ilist.into_py(py));
+    result.push(flist.into_py(py));
+    result.push(slist.into_py(py));
+    return result;
+}

ulist/src/lib.rs

@@ -4,6 +4,7 @@ mod control_flow;
 mod floatings;
 mod index;
 mod integers;
+mod io;
 mod non_float;
 mod numerical;
 mod string;
@@ -29,6 +30,7 @@ fn ulist(_py: Python, m: &PyModule) -> PyResult<()> {
     m.add_function(wrap_pyfunction!(select_float, m)?)?;
     m.add_function(wrap_pyfunction!(select_int, m)?)?;
     m.add_function(wrap_pyfunction!(select_string, m)?)?;
+    m.add_function(wrap_pyfunction!(io::read_csv, m)?)?;
 
     Ok(())
 }