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pub(crate) fn js_max(a: f64, b: f64) -> f64 {
if a.is_nan() || b.is_nan() { f64::NAN } else { a.max(b) }
}
pub(crate) fn js_min(a: f64, b: f64) -> f64 {
if a.is_nan() || b.is_nan() { f64::NAN } else { a.min(b) }
}
pub(crate) fn js_parse_float(value: &str) -> f64 {
let trimmed = value.trim_start();
let (sign, rest) = match trimmed.strip_prefix('-') {
Some(rest) => (-1.0, rest),
None => (1.0, trimmed.strip_prefix('+').unwrap_or(trimmed)),
};
if rest.starts_with("Infinity") {
return sign * f64::INFINITY;
}
let bytes = rest.as_bytes();
let mut end = 0;
let mut seen_digit = false;
let mut seen_dot = false;
while end < bytes.len() {
match bytes[end] {
b'0'..=b'9' => {
seen_digit = true;
end += 1;
}
b'.' if !seen_dot => {
seen_dot = true;
end += 1;
}
_ => break,
}
}
if !seen_digit {
return f64::NAN;
}
let mantissa_end = end;
if end < bytes.len() && (bytes[end] == b'e' || bytes[end] == b'E') {
let mut exponent_end = end + 1;
if exponent_end < bytes.len()
&& (bytes[exponent_end] == b'+' || bytes[exponent_end] == b'-')
{
exponent_end += 1;
}
let digits_start = exponent_end;
while exponent_end < bytes.len() && bytes[exponent_end].is_ascii_digit() {
exponent_end += 1;
}
if exponent_end > digits_start {
end = exponent_end;
} else {
end = mantissa_end;
}
}
sign * rest[..end].parse::<f64>().unwrap_or(f64::NAN)
}
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