The anthology module

The anthology module was added to run built-in commands. The 'cd' and
'exit' built-ins were moved from the main recite() loop to this module.
Additionally, the 'export' and 'source' built-ins were added.

1 files changed, 20 insertions, 0 deletions

diff --git a/src/poem/anthology/cd.rs b/src/poem/anthology/cd.rs
new file mode 100644
index 0000000..3b48f60
--- /dev/null
+++ b/src/poem/anthology/cd.rs
@@ -0,0 +1,20 @@
+use crate::poem::Verse;
+
+pub fn incant(verse: &Verse) -> i32 {
+    let path = match verse.clause() {
+        Some(path) => path[0].to_string(),
+        None => env!("HOME").to_string(),
+    };
+
+    match std::env::set_current_dir(&path) {
+        Ok(_) => 0,
+        Err(e) => {
+            eprintln!(
+                "cd: unable to change into {}: {}",
+                path,
+                e.to_string().to_lowercase()
+            );
+            1
+        }
+    }
+}