Implement REQUIRE (Forth 2012)

[pforth] / fth / require.fth

diff --git a/fth/require.fth b/fth/require.fth
new file mode 100644 (file)
index 0000000..c18d8c4
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+++ b/fth/require.fth
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+\ REQUIRE and REQUIRED
+\
+\ This code is part of pForth.
+\
+\ The pForth software code is dedicated to the public domain,
+\ and any third party may reproduce, distribute and modify
+\ the pForth software code or any derivative works thereof
+\ without any compensation or license.  The pForth software
+\ code is provided on an "as is" basis without any warranty
+\ of any kind, including, without limitation, the implied
+\ warranties of merchantability and fitness for a particular
+\ purpose and their equivalents under the laws of any jurisdiction.
+
+private{
+
+\ Has the file with name C-ADDR/U already been included?
+\
+\ This searches the "::::<filename>" marker created by INCLUDED.  This
+\ works for now, but may break if pForth ever receives wordlists.
+: INCLUDED? ( c-addr u -- flag )
+    s" ::::" here place         ( c-addr u )
+    here $append                ( )
+    here latest findnfa.from    ( x found? )
+    nip
+;
+
+\ FIXME: use real PARSE-NAME when available
+: (PARSE-NAME) ( "word" -- c-addr u ) bl parse-word ;
+
+}private
+
+: REQUIRED ( i*x c-addr u -- j*x ) 2dup included? IF 2drop ELSE included THEN ;
+: REQUIRE ( i*x "name" -- i*x ) (parse-name) required ;
+
+privatize