add HtmlDefaultTheme to pretty_print

mers_lib/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "mers_lib"
-version = "0.8.22"
+version = "0.8.23"
 edition = "2021"
 license = "MIT OR Apache-2.0"
 description = "library to use the mers language in other projects"
@@ -9,7 +9,7 @@ readme = "README.md"
 repository = "https://github.com/Dummi26/mers"
 
 [features]
-default = ["parse"]
+default = ["parse", "pretty-print", "ecolor-html"]
 
 # for parsing and running mers code (for most situations: just enable parse)
 parse = ["run"]

mers_lib/src/pretty_print.rs

@@ -1,4 +1,4 @@
-use std::{io::Write, process::exit, sync::Arc};
+use std::{io::Write, sync::Arc};
 
 use crate::{
     errors::CheckError,
@@ -10,7 +10,7 @@ use crate::{
 pub fn pretty_print(src: Source) {
     if let Err(e) = pretty_print_to(src, &mut std::io::stdout(), DefaultTheme) {
         eprintln!("{e:?}");
-        exit(28);
+        std::process::exit(28);
     }
 }
 
@@ -95,6 +95,35 @@ impl ThemeGen for DefaultTheme {
     }
 }
 
+#[cfg(feature = "ecolor-html")]
+pub struct HtmlDefaultTheme;
+#[cfg(feature = "ecolor-html")]
+impl ThemeGen for HtmlDefaultTheme {
+    type C = FColor;
+    type T = String;
+    fn color(&self, text: &str, color: FColor, t: &mut String) {
+        if let Some(color) = map_color(color) {
+            let color = match color {
+                AbstractColor::Gray => "Gray",
+                AbstractColor::Green => "Green",
+                AbstractColor::Red => "Crimson",
+                AbstractColor::Blue => "RoyalBlue",
+                AbstractColor::Cyan => "DarkCyan",
+            };
+            t.push_str("<span style=\"color:");
+            t.push_str(color);
+            t.push_str(";\">");
+            self.nocolor(text, t);
+            t.push_str("</span>");
+        } else {
+            self.nocolor(text, t);
+        }
+    }
+    fn nocolor(&self, text: &str, t: &mut String) {
+        html_escape::encode_text_to_string(text, t);
+    }
+}
+
 // const FColor::Comment: Color = Color::BrightBlack;
 // const FColor::Variable: Color = Color::Green;
 // const FColor::Variable_Ref: Color = Color::Green;