    const std = @import("std");
    const parse = @import("parse.zig");
    const convertFast = @import("convert_fast.zig").convertFast;
    const convertEiselLemire = @import("convert_eisel_lemire.zig").convertEiselLemire;
    const convertSlow = @import("convert_slow.zig").convertSlow;
    const convertHex = @import("convert_hex.zig").convertHex;

    const optimize = true;

    pub const ParseFloatError = error{
        InvalidCharacter,
    };

    pub fn parseFloat(comptime T: type, s: []const u8) ParseFloatError!T {
        if (@typeInfo(T) != .Float) {
            @compileError("Cannot parse a float into a non-floating point type.");
        }

        if (T == f80) {
            @compileError("TODO support parsing float to f80");
        }

        if (s.len == 0) {
            return error.InvalidCharacter;
        }

        var i: usize = 0;
        const negative = s[i] == '-';
        if (s[i] == '-' or s[i] == '+') {
            i += 1;
        }
        if (s.len == i) {
            return error.InvalidCharacter;
        }

        const n = parse.parseNumber(T, s[i..], negative) orelse {
            return parse.parseInfOrNan(T, s[i..], negative) orelse error.InvalidCharacter;
        };

        if (n.hex) {
            return convertHex(T, n);
        }

        if (optimize) {
            if (convertFast(T, n)) |f| {
                return f;
            }

            if (T == f16 or T == f32 or T == f64) {
                // If significant digits were truncated, then we can have rounding error

                // only if `mantissa + 1` produces a different result. We also avoid

                // redundantly using the Eisel-Lemire algorithm if it was unable to

                // correctly round on the first pass.

                if (convertEiselLemire(T, n.exponent, n.mantissa)) |bf| {
                    if (!n.many_digits) {
                        return bf.toFloat(T, n.negative);
                    }
                    if (convertEiselLemire(T, n.exponent, n.mantissa + 1)) |bf2| {
                        if (bf.eql(bf2)) {
                            return bf.toFloat(T, n.negative);
                        }
                    }
                }
            }
        }

        // Unable to correctly round the float using the Eisel-Lemire algorithm.

        // Fallback to a slower, but always correct algorithm.

        return convertSlow(T, s[i..]).toFloat(T, negative);
    }