Initial commit

1 files changed, 69 insertions, 0 deletions

diff --git a/unix/boot/spp/rpp/rpprat/pbstr.r b/unix/boot/spp/rpp/rpprat/pbstr.r
new file mode 100644
index 00000000..9c2234de
--- /dev/null
+++ b/unix/boot/spp/rpp/rpprat/pbstr.r
@@ -0,0 +1,69 @@
+include  defs
+
+# PBSTR -- Push string back onto input.
+
+subroutine pbstr (s)
+
+character s(ARB)			# string to be pushed back.
+integer lenstr, i
+integer length
+
+#begin
+	lenstr = length (s)
+	
+	# We are called to push back tokens returned by GTOK, which converts
+	# the ratfor relational operators >, >=, &, etc. into their Fortran
+	# equivalents .gt., .ge., .and., and so on.  This conversion must be
+	# reversed in the push back to prevent macro expansion from operating
+	# on the strings "gt", "ge, "and", etc.  This is a stupid way to
+	# handle this but this ratfor code (which was free) is a hopeless mess
+	# already anyhow.
+
+	if (s(1) == PERIOD & s(lenstr) == PERIOD)
+	    if (lenstr == 4) {
+		if (s(2) == LETG) {
+		    if (s(3) == LETT) {			# .gt.
+			call putbak (GREATER)
+			return
+		    } else if (s(3) == LETE) {		# .ge.
+			# Note chars are pushed back in
+			# reverse order.
+			call putbak (EQUALS)
+			call putbak (GREATER)
+			return
+		    }
+		} else if (s(2) == LETL) {
+		    if (s(3) == LETT) {			# .lt.
+			call putbak (LESS)
+			return
+		    } else if (s(3) == LETE) {		# .le.
+			call putbak (EQUALS)
+			call putbak (LESS)
+			return
+		    }
+		} else if (s(2) == LETE & s(3) == LETQ) {
+		    call putbak (EQUALS)		# .eq.
+		    call putbak (EQUALS)
+		    return
+		} else if (s(2) == LETN & s(3) == LETE) {
+		    call putbak (EQUALS)		# .ne.
+		    call putbak (BANG)
+		    return
+		} else if (s(2) == LETO & s(3) == LETR) {
+		    call putbak (OR)			# .or.
+		    return
+		}
+	    } else if (lenstr == 5) {
+		if (s(2) == LETN & s(3) == LETO & s(4) == LETT) {
+		    call putbak (BANG)			# .not.
+		    return
+		} else if (s(2) == LETA & s(3) == LETN & s(4) == LETD) {
+		    call putbak (AND)			# .and.
+		    return
+		}
+	    }
+
+	# Push back an arbitrary string.
+	for (i=lenstr;  i > 0;  i=i-1)
+	    call putbak (s(i))
+end