lpython_builtin.py

from lpython import (i8, i16, i32, i64, f32, f64, c32, c64, overload, u8,
                     u16, u32, u64)
#from sys import exit

#: abs() as a generic procedure.
#: supported types for argument:
#: i8, i16, i32, i64, f32, f64, bool, c32, c64
@overload
def abs(x: f64) -> f64:
    """
    Return the absolute value of `x`.
    """
    result: f64
    if x >= 0.0:
        result = x
    else:
        result = -x
    return result

@overload
def abs(x: f32) -> f32:
    if x >= f32(0.0):
        return x
    else:
        return -x

@overload
def abs(x: i8) -> i8:
    if x >= i8(0):
        return x
    else:
        return -x

@overload
def abs(x: i16) -> i16:
    if x >= i16(0):
        return x
    else:
        return -x

@overload
def abs(x: i32) -> i32:
    if x >= 0:
        return x
    else:
        return -x

@overload
def abs(x: i64) -> i64:
    if x >= i64(0):
        return x
    else:
        return -x

@overload
def abs(b: bool) -> i32:
    if b:
        return 1
    else:
        return 0

@overload
def abs(c: c32) -> f32:
    a: f32
    b: f32
    a = c.real
    b = c.imag
    return f32((a**f32(2) + b**f32(2))**f32(1/2))

@overload
def abs(c: c64) -> f64:
    a: f64
    b: f64
    a = c.real
    b = c.imag
    return (a**2.0 + b**2.0)**(1/2)

@interface
def len(s: str) -> i32:
    """
    Return the length of the string `s`.
    """
    pass

#: pow() as a generic procedure.
#: supported types for arguments:
#: (i32, i32), (i64, i64), (f64, f64),
#: (f32, f32), (i32, f64), (f64, i32),
#: (i32, f32), (f32, i32), (bool, bool), (c32, i32)
@overload
def pow(x: i32, y: i32) -> f64:
    """
    Returns x**y.
    """
    return f64(x**y)

@overload
def pow(x: i64, y: i64) -> f64:
    return f64(x**y)

@overload
def pow(x: f32, y: f32) -> f32:
    return x**y

@overload
def pow(x: f64, y: f64) -> f64:
    """
    Returns x**y.
    """
    return x**y

@overload
def pow(x: i32, y: f32) -> f32:
    return f32(x)**y

@overload
def pow(x: f32, y: i32) -> f32:
    return x**f32(y)

@overload
def pow(x: i32, y: f64) -> f64:
    return f64(x)**y

@overload
def pow(x: f64, y: i32) -> f64:
    return x**f64(y)

@overload
def pow(x: bool, y: bool) -> i32:
    if y and not x:
        return 0

    return 1

@overload
def pow(c: c32, y: i32) -> c32:
    return c**c32(y)

# sum
# supported data types: i32, i64, f32, f64

@overload
def sum(arr: list[i32]) -> i32:
    """
    Sum of the elements of `arr`.
    """
    sum: i32
    sum = 0

    i: i32
    for i in range(len(arr)):
        sum += arr[i]
    return sum

@overload
def sum(arr: list[i64]) -> i64:
    """
    Sum of the elements of `arr`.
    """
    sum: i64
    sum = i64(0)

    i: i32
    for i in range(len(arr)):
        sum += arr[i]
    return sum

@overload
def sum(arr: list[f32]) -> f32:
    """
    Sum of the elements of `arr`.
    """
    sum: f32
    sum = f32(0.0)

    i: i32
    for i in range(len(arr)):
        sum += arr[i]
    return sum

@overload
def sum(arr: list[f64]) -> f64:
    """
    Sum of the elements of `arr`.
    """
    sum: f64
    sum = 0.0

    i: i32
    for i in range(len(arr)):
        sum += arr[i]
    return sum

def bin(n: i32) -> str:
    """
    Returns the binary representation of an integer `n`.
    """
    if n == 0:
        return '0b0'
    prep: str
    prep = '0b'
    n_: i32
    n_ = n
    if n_ < 0:
        n_ = -n_
        prep = '-0b'
    res: str
    res = ''
    if (n_ - (n_ // 2)*2) == 0:
        res += '0'
    else:
        res += '1'
    while n_ > 1:
        n_ = (n_ // 2)
        if (n_ - (n_ // 2)*2) == 0:
            res += '0'
        else:
            res += '1'
    return prep + res[::-1]


def hex(n: i32) -> str:
    """
    Returns the hexadecimal representation of an integer `n`.
    """
    hex_values: list[str]
    hex_values = ['0', '1', '2', '3', '4', '5', '6', '7',
                  '8', '9', 'a', 'b', 'c', 'd', 'e', 'f']
    if n == 0:
        return '0x0'
    prep: str
    prep = '0x'
    n_: i32
    n_ = n
    if n_ < 0:
        prep = '-0x'
        n_ = -n_
    res: str
    res = ""
    remainder: i32
    while n_ > 0:
        remainder = n_ - (n_ // 16)*16
        n_ -= remainder
        n_ = (n_ // 16)
        res += hex_values[remainder]
    return prep + res[::-1]


def oct(n: i32) -> str:
    """
    Returns the octal representation of an integer `n`.
    """
    _values: list[str]
    _values = ['0', '1', '2', '3', '4', '5', '6', '7',
               '8', '9', 'a', 'b', 'c', 'd', 'e', 'f']
    if n == 0:
        return '0o0'
    prep: str
    prep = '0o'
    n_: i32
    n_ = n
    if n_ < 0:
        prep = '-0o'
        n_ = -n_
    res: str
    res = ""
    remainder: i32
    while n_ > 0:
        remainder = n_ - (n_ // 8)*8
        n_ -= remainder
        n_ = (n_ // 8)
        res += _values[remainder]
    return prep + res[::-1]

#: round() as a generic procedure.
#: supported types for argument:
#: i8, i16, i32, i64, f32, f64, bool
@overload
def round(value: f64) -> i32:
    """
    Rounds a floating point number to the nearest integer.
    """
    i: i32
    i = i32(value)
    f: f64
    f = abs(value - f64(i))
    if f < 0.5:
        return i
    elif f > 0.5:
        return i + 1
    else:
        if i - (i // 2) * 2 == 0:
            return i
        else:
            return i + 1

@overload
def round(value: f32) -> i32:
    i: i32
    i = i32(value)
    f: f64
    f = f64(abs(value - f32(i)))
    if f < 0.5:
        return i
    elif f > 0.5:
        return i + 1
    else:
        if i - (i // 2) * 2 == 0:
            return i
        else:
            return i + 1

@overload
def round(value: i32) -> i32:
    return value

@overload
def round(value: i64) -> i64:
    return value

@overload
def round(value: i8) -> i8:
    return value

@overload
def round(value: i16) -> i16:
    return value

@overload
def round(b: bool) -> i32:
    return abs(b)

#: complex() as a generic procedure.
#: supported types for arguments:
#: (f64, f64), (f32, f64), (f64, f32), (f32, f32),
#: (i32, i32), (i64, i64), (i32, i64), (i64, i32)


@interface
@overload
def complex() -> c64:
    return c64(0) + c64(0)*1j


@interface
@overload
def complex(x: f64) -> c64:
    return c64(x) + c64(0)*1j

@interface
@overload
def complex(x: i32) -> c32:
    return c32(x) + c32(0)*c32(1j)

@interface
@overload
def complex(x: f32) -> c32:
    return c32(x) + c32(0)*c32(1j)

@interface
@overload
def complex(x: i64) -> c64:
    return c64(x) + c64(0)*1j

@interface
@overload
def complex(x: f64, y: f64) -> c64:
    """
    Return a complex number with the given real and imaginary parts.
    """
    return c64(x) + c64(y)*1j

@interface
@overload
def complex(x: f32, y: f32) -> c32:
    return c32(x) + c32(y)*c32(1j)

@interface
@overload
def complex(x: f32, y: f64) -> c64:
    return c64(x) + c64(y)*1j

@interface
@overload
def complex(x: f64, y: f32) -> c64:
    return c64(x) + c64(y)*1j

@interface
@overload
def complex(x: i32, y: i32) -> c64:
    return c64(x) + c64(y)*1j

@interface
@overload
def complex(x: i64, y: i64) -> c64:
    return c64(x) + c64(y)*1j

@interface
@overload
def complex(x: i32, y: i64) -> c64:
    return c64(x) + c64(y)*1j

@interface
@overload
def complex(x: i64, y: i32) -> c64:
    return c64(x) + c64(y)*1j

@interface
@overload
def complex(x: i32, y: f64) -> c64:
    return c64(x) + c64(y)*1j

@interface
@overload
def complex(x: f64, y: i32) -> c64:
    return c64(x) + c64(y)*1j

@interface
def divmod(x: i32, y: i32) -> tuple[i32, i32]:
    """
    Return the tuple (x//y, x%y).
    """
    if y == 0:
        raise ZeroDivisionError("Integer division or modulo by zero not possible")
    t: tuple[i32, i32]
    t = ((x // y), _mod(x, y))
    return t


def lbound(x: i32[:], dim: i32) -> i32:
    pass


def ubound(x: i32[:], dim: i32) -> i32:
    pass

@overload
def _lpython_imag(x: c64) -> f64:
    return x.imag

@overload
def _lpython_imag(x: c32) -> f32:
    return x.imag


@overload
def _mod(a: i8, b: i8) -> i8:
    return a - (a // b)*b

@overload
def _mod(a: i16, b: i16) -> i16:
    return a - (a // b)*b

@overload
def _mod(a: i32, b: i32) -> i32:
    return a - (a // b)*b

@overload
def _mod(a: u8, b: u8) -> u8:
    return a - (a // b)*b

@overload
def _mod(a: u16, b: u16) -> u16:
    return a - (a // b)*b

@overload
def _mod(a: u32, b: u32) -> u32:
    return a - (a // b)*b

@overload
def _mod(a: f32, b: f32) -> f32:
    return a - (a // b)*b

@overload
def _mod(a: u64, b: u64) -> u64:
    return a - (a // b)*b

@overload
def _mod(a: i64, b: i64) -> i64:
    return a - (a // b)*b

@overload
def _mod(a: f64, b: f64) -> f64:
    return a - (a // b)*b


@overload
def max(a: i32, b: i32) -> i32:
    if a > b:
        return a
    else:
        return b

@overload
def max(a: i32, b: i32, c: i32) -> i32:
    res: i32 = a
    if b > res:
        res = b
    if c > res:
        res = c
    return res

@overload
def max(a: f64, b: f64, c: f64) -> f64:
    res: f64 =a
    if b - res > 1e-6:
        res = b
    if c - res > 1e-6:
        res = c
    return res

@overload
def max(a: f64, b: f64) -> f64:
    if a - b > 1e-6:
        return a
    else:
        return b

@overload
def min(a: i32, b: i32) -> i32:
    if a < b:
        return a
    else:
        return b

@overload
def min(a: i32, b: i32, c: i32) -> i32:
    res: i32 = a
    if b < res:
        res = b
    if c < res:
        res = c
    return res

@overload
def min(a: f64, b: f64, c: f64) -> f64:
    res: f64 = a
    if res - b > 1e-6:
        res = b
    if res - c > 1e-6:
        res = c
    return res

@overload
def min(a: f64, b: f64) -> f64:
    if b - a > 1e-6:
        return a
    else:
        return b


@overload
def _floor(x: f64) -> i64:
    r: i64
    r = int(x)
    if x >= f64(0) or x == f64(r):
        return r
    return r - i64(1)

@overload
def _floor(x: f32) -> i32:
    r: i32
    r = i32(x)
    if x >= f32(0) or x == f32(r):
        return r
    return r - 1


@overload
def _mod(a: i32, b: i32) -> i32:
    """
    Returns a%b
    """
    return a - i32(_floor(a/b))*b


@overload
def _mod(a: i64, b: i64) -> i64:
    """
    Returns a%b
    """
    r: i64
    r = _floor(a/b)
    return a - r*b


@overload
def pow(x: i32, y: i32, z: i32) -> i32:
    """
    Return `x` raised to the power `y`.
    """
    if y < 0:
        raise ValueError('y should be nonnegative')
    result: i32
    result = _mod(x**y, z)
    return result


@overload
def pow(x: i64, y: i64, z: i64) -> i64:
    """
    Return `x` raised to the power `y`.
    """
    if y < i64(0):
        raise ValueError('y should be nonnegative')
    result: i64
    result = _mod(x**y, z)
    return result

@overload
def _lpython_str_capitalize(x: str) -> str:
    if len(x) == 0:
        return x
    i:str
    res:str = ""
    for i in x:
        if ord(i) >= 65 and ord(i) <= 90:  # Check if uppercase
            res += chr(ord(i) + 32)  # Convert to lowercase using ASCII values
        else:
            res += i

    val: i32
    val = ord(res[0])
    if val >= ord('a') and val <= ord('z'):
        val -= 32
    res = chr(val) + res[1:]
    return res


@overload
def _lpython_str_count(s: str, sub: str) -> i32:
    s_len :i32; sub_len :i32; flag: bool; _len: i32;
    count: i32; i: i32;
    lps: list[i32] = []
    s_len = len(s)
    sub_len = len(sub)

    if sub_len == 0:
        return s_len + 1

    count = 0

    for i in range(sub_len):
        lps.append(0)

    i = 1
    _len = 0
    while i < sub_len:
        if sub[i] == sub[_len]:
            _len += 1
            lps[i] = _len
            i += 1
        else:
            if _len != 0:
                _len = lps[_len - 1]
            else:
                lps[i] = 0
                i += 1

    j: i32
    j = 0
    i = 0
    while (s_len - i) >= (sub_len - j):
        if sub[j] == s[i]:
            i += 1
            j += 1
        if j == sub_len:
            count += 1
            j = lps[j - 1]
        elif i < s_len and sub[j] != s[i]:
            if j != 0:
                j = lps[j - 1]
            else:
                i = i + 1

    return count


@overload
def _lpython_str_lower(x: str) -> str:
    res: str
    res = ""
    i:str
    for i in x:
        if ord('A') <= ord(i) and ord(i) <= ord('Z'):
            res += chr(ord(i) +32)
        else:
            res += i
    return res

@overload
def _lpython_str_upper(x: str) -> str:
    res: str
    res = ""
    i:str
    for i in x:
        if ord('a') <= ord(i) and ord(i) <= ord('z'):
            res += chr(ord(i) -32)
        else:
            res += i
    return res

@overload
def _lpython_str_join(s:str, lis:list[str]) -> str:
    if len(lis) == 0: return ""
    res:str = lis[0]
    i:i32
    for i in range(1, len(lis)):
        res += s + lis[i]
    return res

def _lpython_str_isalpha(s: str) -> bool:
    ch: str
    if len(s) == 0: return False
    for ch in s:
        ch_ord: i32 = ord(ch)
        if 65 <= ch_ord and ch_ord <= 90:
            continue
        if 97 <= ch_ord and ch_ord <= 122:
            continue
        return False
    return True

def _lpython_str_isalnum(s: str) -> bool:
    ch: str
    if len(s) == 0: return False
    for ch in s:
        ch_ord: i32 = ord(ch)
        if 65 <= ch_ord and ch_ord <= 90:
            continue
        if 97 <= ch_ord and ch_ord <= 122:
            continue
        if 48 <= ch_ord and ch_ord <= 57:
            continue
        return False
    return True

def _lpython_str_isnumeric(s: str) -> bool:
    ch: str
    if len(s) == 0: return False
    for ch in s:
        ch_ord: i32 = ord(ch)
        if 48 <= ch_ord and ch_ord <= 57:
            continue
        return False
    return True

def _lpython_str_title(s: str) -> str:
    result: str = ""
    capitalize_next: bool = True
    ch: str
    for ch in s:
        ch_ord: i32 = ord(ch)
        if ch_ord >= 97  and ch_ord <= 122:
            if capitalize_next:
                result += chr(ord(ch) - ord('a') + ord('A'))
                capitalize_next = False
            else:
                result += ch
        elif ch_ord >= 65 and ch_ord <= 90:
            if capitalize_next:
                result += ch
                capitalize_next = False
            else:
                result += chr(ord(ch) + ord('a') - ord('A'))
        else:
            result += ch
            capitalize_next = True

    return result

def _lpython_str_istitle(s: str) -> bool:
    length: i32 = len(s)

    if length == 0:
        return False  # Empty string is not in title case

    word_start: bool = True  # Flag to track the start of a word
    ch: str
    only_whitespace: bool = True
    for ch in s:
        if ch.isalpha() and (ord('A') <= ord(ch) and ord(ch) <= ord('Z')):
            only_whitespace = False
            if word_start:
                word_start = False
            else:
                return False  # Found an uppercase character in the middle of a word

        elif ch.isalpha() and (ord('a') <= ord(ch) and ord(ch) <= ord('z')):
            only_whitespace = False
            if word_start:
                return False  # Found a lowercase character in the middle of a word
            word_start = False
        else:
            word_start = True

    return True if not only_whitespace else False

@overload
def _lpython_str_find(s: str, sub: str) -> i32:
    s_len :i32; sub_len :i32; flag: bool; _len: i32;
    res: i32; i: i32;
    lps: list[i32] = []
    s_len = len(s)
    sub_len = len(sub)
    flag = False
    res = -1
    if s_len == 0 or sub_len == 0:
        return 0 if sub_len == 0 or (sub_len == s_len) else -1

    for i in range(sub_len):
        lps.append(0)

    i = 1
    _len = 0
    while i < sub_len:
        if sub[i] == sub[_len]:
            _len += 1
            lps[i] = _len
            i += 1
        else:
            if _len != 0:
                _len = lps[_len - 1]
            else:
                lps[i] = 0
                i += 1

    j: i32
    j = 0
    i = 0
    while (s_len - i) >= (sub_len - j) and not flag:
        if sub[j] == s[i]:
            i += 1
            j += 1
        if j == sub_len:
            res = i- j
            flag = True
            j = lps[j - 1]
        elif i < s_len and sub[j] != s[i]:
            if j != 0:
                j = lps[j - 1]
            else:
                i = i + 1

    return res

def _lpython_str_rstrip(x: str) -> str:
    ind: i32
    ind = len(x) - 1
    while ind >= 0 and x[ind] == ' ':
        ind -= 1
    return x[0: ind + 1]

@overload
def _lpython_str_lstrip(x: str) -> str:
    ind :i32
    ind = 0
    while ind < len(x) and x[ind] == ' ':
        ind += 1
    return x[ind :len(x)]

@overload
def _lpython_str_strip(x: str) -> str:
    res :str
    res = _lpython_str_lstrip(x)
    res = _lpython_str_rstrip(res)
    return res

@overload
def _lpython_str_split(x: str) -> list[str]:
    sep: str = ' '
    res: list[str] = []
    start:i32 = 0
    ind: i32
    x_strip: str = _lpython_str_strip(x)
    if (x_strip == ""):
        return res
    while True:
        while (start < len(x_strip) and x_strip[start] == ' '):
            start += 1
        ind = _lpython_str_find(x_strip[start:len(x_strip)], sep)
        if ind == -1:
            res.append(x_strip[start:len(x_strip)])
            break
        else:
            res.append(x_strip[start:start + ind])
            start += ind + len(sep)
    return res

@overload
def _lpython_str_split(x: str, sep:str) -> list[str]:
    if len(sep) == 0:
        raise ValueError('empty separator')
    res: list[str] = []
    start:i32 = 0
    ind: i32
    while True:
        ind = _lpython_str_find(x[start:len(x)], sep)
        if ind == -1:
            res.append(x[start:len(x)])
            break
        else:
            res.append(x[start:start + ind])
            start += ind + len(sep)
    return res

@overload
def _lpython_str_replace(x: str, old:str, new:str) -> str:
    return _lpython_str_replace(x, old, new, len(x))


@overload
def _lpython_str_replace(x: str, old:str, new:str, count: i32) -> str:
    if (old == ""):
        res1: str = ""
        s: str
        for s in x:
            res1 += new + s
        return res1 + new
    res: str = ""
    i: i32 = 0
    ind: i32 = -1
    l: i32 = len(new)
    lo: i32 = len(old)
    lx: i32 = len(x)
    c: i32 = 0
    t: i32 = -1

    while(c<count):
        t = _lpython_str_find(x[i:lx], old)
        if(t==-1):
            break
        ind = i + t
        res = res + x[i:ind] + new
        i = ind + lo
        c = c + 1
    res = res + x[i:lx]
    return res

@overload
def _lpython_str_swapcase(s: str) -> str:
    res :str = ""
    cur: str
    for cur in s:
        if ord(cur) >= ord('a') and ord(cur) <= ord('z'):
            res += chr(ord(cur) - ord('a') + ord('A'))
        elif ord(cur) >= ord('A') and ord(cur) <= ord('Z'):
            res += chr(ord(cur) - ord('A') + ord('a'))
        else:
            res += cur
    return res

@overload
def _lpython_str_startswith(s: str ,sub: str) -> bool:
    res :bool
    res = not (len(s) == 0 and len(sub) > 0)
    i: i32; j: i32
    i = 0; j = 0
    while (i < len(s)) and ((j < len(sub)) and res):
        res = res and (s[i] == sub[j])
        i += 1; j+=1
    if res:
        res = res and (j == len(sub))
    return res

@overload
def _lpython_str_endswith(s: str, suffix: str) -> bool:

    if(len(suffix) > len(s)):
        return False

    i : i32
    i = 0
    while(i < len(suffix)):
        if(suffix[len(suffix) - i - 1] != s[len(s) - i - 1]):
            return False
        i += 1

    return True

@overload
def _lpython_str_partition(s:str, sep: str) -> tuple[str, str, str]:
    """
    Returns a 3-tuple splitted around seperator
    """
    if len(s) == 0:
        raise ValueError('empty string cannot be partitioned')
    if len(sep) == 0:
        raise ValueError('empty separator')
    res : tuple[str, str, str]
    ind : i32
    ind = _lpython_str_find(s, sep)
    if ind == -1:
        res = (s, "", "")
    else:
        res = (s[0:ind], sep, s[ind+len(sep): len(s)])
    return res

@overload
def _lpython_str_islower(s: str) -> bool:
    is_cased_present: bool
    is_cased_present = False
    i:str
    for i in s:
        if (ord(i) >= 97 and ord(i) <= 122) or (ord(i) >= 65 and ord(i) <= 90): # Implies it is a cased letter
            is_cased_present = True
            if not(ord(i) >= 97 and ord(i) <= 122): # Not lowercase
                return False
    return is_cased_present

@overload
def _lpython_str_isupper(s: str) -> bool:
    is_cased_present: bool
    is_cased_present = False
    i:str
    for i in s:
        if (ord(i) >= 97 and ord(i) <= 122) or (ord(i) >= 65 and ord(i) <= 90): # Implies it is a cased letter
            is_cased_present = True
            if not(ord(i) >= 65 and ord(i) <= 90): # Not lowercase
                return False
    return is_cased_present

@overload
def _lpython_str_isdecimal(s: str) -> bool:
    if len(s) == 0:
        return False
    i:str
    for i in s:
        if (ord(i) < 48 or ord(i) > 57): # Implies it is not a digit
            return False
    return True

@overload
def _lpython_str_isascii(s: str) -> bool:
    if len(s) == 0:
        return True
    i: str
    for i in s:
        if ord(i) < 0 or ord(i) > 127:
            return False
    return True

def _lpython_str_isspace(s: str) -> bool:
    # A Unicode character is considered a 'whitespace' if it has has a bidirectional
    # type 'WS', 'B' or 'S'; or the category 'Zs'.
    if len(s) == 0:
        return False

    ch: str
    for ch in s:
        if not (ch == " "  or   # SPACE
            ch == "\n"     or   # LINE FEED (LF)
            ch == "\r"     or   # CARRIAGE RETURN (CR)
            ch == "\t"     or   # CHARACTER TABULATION (HT)
            ch == "\v"     or   # VERTICAL TAB (VT)
            ch == "\f"     or   # FORM FEED (FF)
            ch == "\u00A0" or   # NO-BREAK SPACE
            ch == "\u1680" or   # OGHAM SPACE MARK
            ch == "\u2000" or   # EN QUAD
            ch == "\u2001" or   # EM QUAD
            ch == "\u2002" or   # EN SPACE
            ch == "\u2003" or   # EM SPACE
            ch == "\u2004" or   # THREE-PER-EM SPACE
            ch == "\u2005" or   # FOUR-PER-EM SPACE
            ch == "\u2006" or   # SIX-PER-EM SPACE
            ch == "\u2007" or   # FIGURE SPACE
            ch == "\u2008" or   # PUNCTUATION SPACE
            ch == "\u2009" or   # THIN SPACE
            ch == "\u200A" or   # HAIR SPACE
            ch == "\u2028" or   # LINE SEPARATOR
            ch == "\u2029" or   # PARAGRAPH SEPARATOR
            ch == "\u202F" or   # NARROW NO-BREAK SPACE
            ch == "\u205F" or   # MEDIUM MATHEMATICAL SPACE
            ch == "\u3000"      # IDEOGRAPHIC SPACE
        ):
            return False
    return True

@overload
def _lpython_str_center(s: str, width_: i32, fillchar: str) -> str:
    """
    Return centered in a string of length width.
    Padding is done using the specified fillchar (default is an ASCII space).
    The original string is returned if width is less than or equal to len(s).
    """
    width: i32 = width_
    if(len(fillchar) != 1):
        raise TypeError("The fill character must be exactly one character long")
    str_len: i32 = len(s)
    if width <= str_len:
        return s
    width -= str_len
    result: str = ""
    left_padding: i32 = i32(width/2) + _mod(width,2)
    i: i32
    for i in range(left_padding):
        result += fillchar
    right_padding: i32 = width - left_padding
    result += s
    for i in range(right_padding):
        result += fillchar
    return result

@overload
def _lpython_str_center(s: str, width: i32) -> str:
    return _lpython_str_center(s, width, ' ')

@overload
def _lpython_str_expandtabs(s: str, tabsize: i32) -> str:
    """
    Return a copy of the string where all tab characters are replaced
    by one or more spaces, depending on the current column and the given tab size.
    """
    if len(s) == 0:
        return s
    col: i32 = 0
    result: str = ""
    c: str
    for c in s:
        if c == '\t':
            if tabsize > 0:
                i: i32
                iterations: i32 = tabsize - _mod(col,tabsize)
                for i in range(iterations):
                    result += ' '
            col = 0
        elif c == '\n' or c == '\r':
            result += c
            col = 0
        else:
            result += c
            col += 1
    return result

@overload
def _lpython_str_expandtabs(s: str) -> str:
    return _lpython_str_expandtabs(s, 8)

def list(s: str) -> list[str]:
    l: list[str] = []
    i: i32
    if len(s) == 0:
        return l
    for i in range(len(s)):
        l.append(s[i])
    return l