Function parse_format_string 

pub fn parse_format_string(fmt: &str) -> Result<Vec<FormatElement<'_>>>

Parses a string to a vector of FormatElement

Takes a printf-style format string fmt

use sprintf::parser::{
    parse_format_string, ConversionSpecifier, ConversionType, FormatElement, NumericParam,
};
let fmt = "Hello %#06x";
let parsed = parse_format_string(fmt).unwrap();
assert_eq!(parsed[0], FormatElement::Verbatim("Hello "));
assert_eq!(
    parsed[1],
    FormatElement::Format(ConversionSpecifier {
        alt_form: true,
        zero_pad: true,
        left_adj: false,
        space_sign: false,
        force_sign: false,
        width: NumericParam::Literal(6),
        precision: NumericParam::Literal(6),
        conversion_type: ConversionType::HexIntLower,
    })
);