Add help messages

src/set.rs

@@ -11,10 +11,17 @@ use std::{collections::HashSet, io::Write, str::FromStr};
 
 #[derive(clap::StructOpt, Debug)]
 pub struct Options {
-    #[clap(min_values = 1, max_values = 3)]
+    #[clap(
+        min_values = 1,
+        max_values = 3,
+        help = "Register operation and operand. Empty register is current selection. Example: 'a-b' or '+b'"
+    )]
     args: Vec<String>,
 
-    #[clap(short = 'T')]
+    #[clap(
+        short = 'T',
+        help = "Do not trim the selections before doing set operations"
+    )]
     no_trim: bool,
     // #[clap(short, long)]
     // regex: Option<Regex>,

src/sort.rs

@@ -5,20 +5,23 @@ use std::{cmp::Ordering, io::Write};
 
 #[derive(clap::StructOpt, Debug)]
 pub struct Options {
-    #[clap(index = 1)]
+    #[clap(index = 1, help = "Optional regex comparison key")]
     regex: Option<Regex>,
-    #[clap(short = 's', long)]
+    #[clap(
+        short = 's',
+        long,
+        help = "Optional register for using subselection ma tching"
+    )]
     subselections_register: Option<char>,
     // TODO: Can we invert a boolean? This name is terrible
-    #[clap(short = 'S', long, parse(try_from_str = invert_bool), default_value_t)]
+    #[clap(short = 'S', long, parse(try_from_str = invert_bool), default_value_t, help = "Do not treat trimmed value of selections when sorting")]
     no_skip_whitespace: bool,
-    #[clap(short, long)]
+    #[clap(short, long, help = "Sort numbers lexicographically")]
     lexicographic_sort: bool,
-    #[clap(short, long)]
+    #[clap(short, long, help = "Reverse sorting")]
     reverse: bool,
-    #[clap(short, long)]
+    #[clap(short, long, help = "Ignore case when sorting")]
     ignore_case: bool,
-    // TODO: Sort by character ([xba] => [abx])
 }
 
 fn invert_bool(s: &str) -> Result<bool, &'static str> {

src/trim.rs

@@ -3,11 +3,15 @@ use std::io::Write;
 
 #[derive(clap::StructOpt, Debug)]
 pub struct Options {
-    #[clap(short, long)]
+    #[clap(short, long, help = "Trim from left")]
     left: bool,
-    #[clap(short, long)]
+    #[clap(short, long, help = "Trim right side")]
     right: bool,
-    #[clap(short, long)]
+    #[clap(
+        short,
+        long,
+        help = "If selection ends in a newline, do not add the newline back after trimming"
+    )]
     no_preserve_newline: bool,
 }
 

src/uniq.rs

@@ -8,12 +8,12 @@ use std::collections::BTreeSet;
 
 #[derive(clap::StructOpt, Debug)]
 pub struct Options {
-    #[clap(index = 1)]
+    #[clap(index = 1, help = "Optional regex to compare unique elements")]
     regex: Option<Regex>,
-    #[clap(short, long)]
+    #[clap(short, long, help = "Ignore the case when comparing")]
     ignore_case: bool,
     // TODO: Can we invert a boolean? This name is terrible
-    #[clap(short = 'S', long)]
+    #[clap(short = 'S', long, help = "Do not skip whitespace when comparing")]
     no_skip_whitespace: bool,
 }
 pub fn uniq(options: &Options) -> Result<String, KakError> {