Add NO_COLOR support

hook.zsh

@@ -1,5 +1,5 @@
 prompt_precmd() {
-  export PS1=$'`prim --ps1 --col $COLUMNS --row $LINES --status $?`'
+  export PS1=$'`prim --ps1 --col $COLUMNS --row $LINES --status $? --pchar ❯`'
   export RPS1=$'`prim --rps1 --col $COLUMNS --row $LINES --status $?`'
 }
 

source/app.d

@@ -14,6 +14,7 @@ Opts defaultOpts() {
   Opts opts;
 
   opts.pathlen = 3;
+  opts.pchar = "|>";
 
   return opts;
 }
@@ -38,10 +39,13 @@ void main(string[] argv) {
     "status", "previous command exit code", &opts.status,
 
     "pathlen", "set length of displayed path", &opts.pathlen,
+    "pchar", "override default prompt character", &opts.pchar,
   );
 
   if (args.helpWanted) {
-    defaultGetoptPrinter("prim", args.options);
+    defaultGetoptPrinter("prim prompt:\n", args.options);
+    writeln("\nEnvironment:\n",
+      "\tNO_COLOR\tsee https://no-color.org");
   }
 
   dorun(opts);
@@ -53,7 +57,7 @@ void dorun(Opts opts) {
   }
 
   if (opts.preexec) {
-    //   preexec(opts).write();
+    preexec(opts).write();
   }
 
   if (opts.rps1) {

source/opt.d

@@ -6,6 +6,7 @@ struct Opts {
   bool preexec;
 
   int pathlen;
+  string pchar;
 
   int col;
   int row;

source/prompt/ps1.d

@@ -21,6 +21,6 @@ string ps1(Opts opt) {
   ps ~= "\n";
 
   ps ~= ("'-(" ~ to!string(opt.status) ~ ") ").set(Color.black); // prompt char
-  ps ~= "|> ".set(Font.bold).set(opt.status == 0 ? Color.green : Color.red);
+  ps ~= (opt.pchar ~ " ").set(Font.bold).set(opt.status == 0 ? Color.green : Color.red);
   return ps;
 }

source/style/package.d

@@ -1,15 +1,22 @@
 module style;
 
 import std.conv;
+import core.stdc.stdlib : getenv;
 
 import style.color;
 
 string set(string s, int code) {
+  if (getenv("NO_COLOR"))
+    return s;
+
   return ("%{\x1b[" ~ to!string(code) ~ "m%}") ~ s ~ (
     "%{\x1b[" ~ to!string((Color.reset + 0)) ~ "m%}");
 }
 
 string set(string s, int code, bool close) {
+  if (getenv("NO_COLOR"))
+    return s;
+
   return ("%{\x1b[" ~ to!string(code) ~ "m%}") ~ s ~ (close ? (
       "%{\x1b[" ~ to!string((Color.reset + 0)) ~ "m%}") : "");
 }