diff --git a/src/iri.rs b/src/iri.rs
index 989c220..268fd69 100644
--- a/src/iri.rs
+++ b/src/iri.rs
@@ -78,11 +78,89 @@ mod ip {
         )(s)
     }
 }
-#[cfg(test)]
 
+struct IRI {
+    scheme: Option<String>,
+    i_hier_part: Option<IHierPart>,
+}
+
+struct IHierPart {
+    authority: Option<Authority>,
+}
+
+struct Authority {
+    user_info: Option<String>,
+    host: Option<Host>,
+    port: Option<String>,
+}
+
+enum Host {
+    IPV4(Vec<u8>),
+    IPV6(Vec<u8>),
+    RegName(String),
+}
+
+mod parser {
+    use crate::prelude::*;
+    fn parse_scheme(s: &str) -> ParserResult<&str> {
+        verify(
+            terminated(
+                take_while1(|c: char| c.is_alphanumeric() || c == '.' || c == '-' || c == '+'),
+                tag(":"),
+            ),
+            |scheme: &str| scheme.starts_with(|c: char| c.is_alphabetic()),
+        )(s)
+    }
+    fn parse_userinfo(s: &str) -> ParserResult<&str> {
+        terminated(
+            terminated(
+                take_while1(|c| c != ':'),
+                opt(preceded(tag(":"), take_while1(|c| c != '@'))), // skip the password
+            ),
+            tag("@"),
+        )(s)
+    }
+    fn parse_i_unreserved(s: &str) -> ParserResult<&str> {
+        fn is_ucs_char(c: char) -> bool {
+            c >= '\u{A0}' && c <= '\u{10FFFF}'
+        }
+        take_while1(|c: char| {
+            c.is_alphanum() || c == '-' || c == '.' || c == '_' || c == '~' || is_ucs_char(c)
+        })(s)
+    }
+    fn parse_sub_delims(s: &str) -> ParserResult<&str> {
+        take_while1(|c| {
+            c == '!'
+                || c == '$'
+                || c == '&'
+                || c == '\''
+                || c == '('
+                || c == ')'
+                || c == '*'
+                || c == '+'
+                || c == ','
+                || c == ';'
+                || c == '='
+        })(s)
+    }
+    fn parse_pct_encoded(s: &str) -> ParserResult<&str> {
+        preceded(
+            tag("%"),
+            verify(take(2usize), |hex: &str| {
+                hex.chars().all(|c| c.is_ascii_hexdigit())
+            }),
+        )(s)
+    }
+}
+#[cfg(test)]
 mod test {
+
     use crate::iri::ip::{parse_ip_v4, parse_ip_v6};
 
+    #[test]
+    fn test_hex_st_to_char() {
+        println!("{}", u8::from_str_radix("3A", 16).unwrap() as char);
+    }
     #[test]
     fn parse_ip_v4_test() {
         assert_eq!(
diff --git a/src/iri_spect.txt b/src/iri_spect.txt
new file mode 100644
index 0000000..02085ba
--- /dev/null
+++ b/src/iri_spect.txt
@@ -0,0 +1,111 @@
+FC 3987         Internationalized Resource Identifiers     January 2005
+
+
+                  / ipath-noscheme
+                  / ipath-empty
+
+   iauthority     = [ iuserinfo "@" ] ihost [ ":" port ]
+   iuserinfo      = *( iunreserved / ncoded / sub-delims / ":" )
+   ihost          = IP-literal / IPv4address / ireg-name
+
+   ireg-name      = *( iunreserved / pct-encoded / sub-delims )
+
+   ipath          = ipath-abempty   ; begins with "/" or is empty
+                  / ipath-absolute  ; begins with "/" but not "//"
+                  / ipath-noscheme  ; begins with a non-colon segment
+                  / ipath-rootless  ; begins with a segment
+                  / ipath-empty     ; zero characters
+
+   ipath-abempty  = *( "/" isegment )
+   ipath-absolute = "/" [ isegment-nz *( "/" isegment ) ]
+   ipath-noscheme = isegment-nz-nc *( "/" isegment )
+   ipath-rootless = isegment-nz *( "/" isegment )
+   ipath-empty    = 0<ipchar>
+
+   isegment       = *ipchar
+   isegment-nz    = 1*ipchar
+   isegment-nz-nc = 1*( iunreserved / pct-encoded / sub-delims
+                        / "@" )
+                  ; non-zero-length segment without any colon ":"
+
+   ipchar         = iunreserved / pct-encoded / sub-delims / ":"
+                  / "@"
+
+   iquery         = *( ipchar / iprivate / "/" / "?" )
+
+   ifragment      = *( ipchar / "/" / "?" )
+
+
+
+   iprivate       = %xE000-F8FF / %xF0000-FFFFD / %x100000-10FFFD
+
+   Some productions are ambiguous.  The "first-match-wins" (a.k.a.
+   "greedy") algorithm applies.  For details, see [RFC3986].
+
+
+
+
+Duerst & Suignard           Standards Track                     [Page 8]
+
+RFC 3987         Internationalized Resource Identifiers     January 2005
+
+
+   The following rules are the same as those in [RFC3986]:
+
+ 
+
+   port           = *DIGIT
+
+   IP-literal     = "[" ( IPv6address / IPvFuture  ) "]"
+
+   IPvFuture      = "v" 1*HEXDIG "." 1*( unreserved / sub-delims / ":" )
+
+ 
+
+
+
+
+
+
+   unreserved     = ALPHA / DIGIT / "-" / "." / "_" / "~"
+   reserved       = gen-delims / sub-delims
+   gen-delims     = ":" / "/" / "?" / "#" / "[" / "]" / "@"
+
+
+
+
+
+DONE:
+   sub-delims     = "!" / "$" / "&" / "'" / "(" / ")"
+                  / "*" / "+" / "," / ";" / "="
+
+   pct-encoded    = "%" HEXDIG HEXDIG
+   iunreserved    = ALPHA / DIGIT / "-" / "." / "_" / "~" / ucschar
+
+   ucschar        = %xA0-D7FF / %xF900-FDCF / %xFDF0-FFEF
+                  / %x10000-1FFFD / %x20000-2FFFD / %x30000-3FFFD
+                  / %x40000-4FFFD / %x50000-5FFFD / %x60000-6FFFD
+                  / %x70000-7FFFD / %x80000-8FFFD / %x90000-9FFFD
+                  / %xA0000-AFFFD / %xB0000-BFFFD / %xC0000-CFFFD
+                  / %xD0000-DFFFD / %xE1000-EFFFD
+
+  scheme         = ALPHA *( ALPHA / DIGIT / "+" / "-" / "." )
+     dec-octet      = DIGIT                 ; 0-9
+                  / %x31-39 DIGIT         ; 10-99
+                  / "1" 2DIGIT            ; 100-199
+                  / "2" %x30-34 DIGIT     ; 200-249
+                  / "25" %x30-35          ; 250-255
+                  
+   IPv4address    = dec-octet "." dec-octet "." dec-octet "." dec-octet
+   
+   IPv6address    =                            6( h16 ":" ) ls32
+                  /                       "::" 5( h16 ":" ) ls32
+                  / [               h16 ] "::" 4( h16 ":" ) ls32
+                  / [ *1( h16 ":" ) h16 ] "::" 3( h16 ":" ) ls32
+                  / [ *2( h16 ":" ) h16 ] "::" 2( h16 ":" ) ls32
+                  / [ *3( h16 ":" ) h16 ] "::"    h16 ":"   ls32
+                  / [ *4( h16 ":" ) h16 ] "::"              ls32
+                  / [ *5( h16 ":" ) h16 ] "::"              h16
+                  / [ *6( h16 ":" ) h16 ] "::"
+  h16            = 1*4HEXDIG
+   ls32           = ( h16 ":" h16 ) / IPv4address
diff --git a/src/lib.rs b/src/lib.rs
index d201498..fb8da27 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -19,7 +19,7 @@ pub mod prelude {
             is_alphanumeric, is_space,
         },
         combinator::{
-            all_consuming, cut, eof, map, map_parser, map_res, opt, peek, recognize, value,
+            all_consuming, cut, eof, map, map_parser, map_res, opt, peek, recognize, value, verify,
         },
         error::{make_error, Error, ErrorKind},
         multi::{many0, separated_list0, separated_list1},