From 517b376231b126f823bb017a2619cdac83270714 Mon Sep 17 00:00:00 2001
From: Pragmatic Software <pragma78@gmail.com>
Date: Mon, 20 Jul 2020 13:37:41 -0700
Subject: [PATCH] Plang can now be used with persistent state via `plangrepl`

---
 Plugins/Plang.pm | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/Plugins/Plang.pm b/Plugins/Plang.pm
index 23ee8cde..f8569090 100644
--- a/Plugins/Plang.pm
+++ b/Plugins/Plang.pm
@@ -58,6 +58,9 @@ sub initialize {
 
     # register the `plang` command
     $self->{pbot}->{commands}->register(sub { $self->cmd_plang(@_) }, "plang", 0);
+
+    # register the `plangrepl` command (does not reset environment)
+    $self->{pbot}->{commands}->register(sub { $self->cmd_plangrepl(@_) }, "plangrepl", 0);
 }
 
 sub unload {
@@ -81,6 +84,22 @@ sub cmd_plang {
     return length $self->{output} ? $self->{output} : "No output.";
 }
 
+sub cmd_plangrepl {
+    my ($self, $context) = @_;
+
+    my $usage = "Usage: plangrepl <code>; see https://github.com/pragma-/Plang";
+    return $usage if not length $context->{arguments};
+
+    $self->{output} = "";  # collect output of the embedded Plang program
+    my $result = $self->{plang}->interpret_string($context->{arguments}, repl => 1);
+
+    # check to see if we need to append final result to output
+    $self->{output} .= $self->{plang}->{interpreter}->output_value($result, repl => 1) if defined $result->[1];
+
+    # return the output
+    return length $self->{output} ? $self->{output} : "No output.";
+}
+
 # overridden `print` built-in
 
 sub print_override {