Issue #407 - Add the ctxoffset ALU function

manpage

@@ -973,6 +973,10 @@ does not. When no
 .I CONTEXT
 is active, returns the same value as
 .B recno().
+.IP "ctxoffset()" 3
+Returns the current effective context offset. When no
+.I CONTEXT
+is active, returns 0.
 .IP "record()" 3
 Returns the entire input record. Equivalent to 
 .B range(1,-1)

specs/docs/alu_adv.md

@@ -165,6 +165,7 @@ All three regular expression functions have an argument called `matchFlags`. Thi
 | `range(n,m)` | Returns the substring from the *n*-th character (default first) to the *m*-th character (default last) |
 | `recno()` | Returns the number of the currently read record. If the `READ` or `READSTOP` keywords are used this may be greater than `number()` |
 | `ctxrecno()` | Returns the record number of the record that input parts work on. This is similar to `recno()`, but considers rolling context, which `recno()` does not. |
+| `ctxoffset()` | Returns the current effective context offset. Returns 0 when no `CONTEXT` is in effect. |
 | `record()` | Returns the entire input record. Equivalent to `@!`. |
 | `cfrecord()` | Returns the entire input record, disregarding rolling context. Same as `record()` when `CONTEXT` is not in effect. Equivalent to `@@`. |
 | `word(n)` | Returns the *n*-th word |

specs/src/test/ProcessingTest.cc

@@ -1124,6 +1124,10 @@ int main(int argc, char** argv)
 		"    Using cfrecord():   But I can't help falling in love with you";
 	VERIFY2(spec, strm.c_str(), res.c_str());   // TEST #260
 
+	// ctxoffset() function test
+	spec = "PRINT 'ctxoffset()' 1  CONTEXT +1  PRINT 'ctxoffset()' NW  CONTEXT -1  PRINT 'ctxoffset()' NW";
+	VERIFY2(spec, "x", "0 1 -1"); // TEST #261
+
 	if (errorCount) {
 		std::cout << '\n' << errorCount << '/' << testCount << " tests failed.\n";
 		std::cout << "Failed tests: ";

specs/src/utils/aluFunctions.cc

@@ -419,6 +419,11 @@ PValue AluFunc_ctxrecno()
 	return mkValue(g_pStateQueryAgent->getRecordCount() + g_pStateQueryAgent->getContextOffset());
 }
 
+PValue AluFunc_ctxoffset()
+{
+	return mkValue(g_pStateQueryAgent->getContextOffset());
+}
+
 PValue AluFunc_eof()
 {
 	bool isRunOut = g_pStateQueryAgent->isEOF();

specs/src/utils/aluFunctions.h

@@ -42,6 +42,8 @@
 			"() - Returns the record number of the current record.","Increments with every READ or READSTOP.") \
 	X(ctxrecno,       0, ALUFUNC_REGULAR,      true,  \
 			"() - Returns the record number of the record that input parts work on.","This is similar to recno, but considers rolling context, which recno does not.") \
+	X(ctxoffset,      0, ALUFUNC_REGULAR,      true,  \
+			"() - Returns the current effective context offset.","Returns 0 when no CONTEXT is in effect.") \
 	X(number,         0, ALUFUNC_REGULAR,      true,  \
 			"() - Returns the number of times this specification has restarted","Does not increment with READ or READSTOP. Otherwise similar to recno().") \
 	X(eof,            0, ALUFUNC_REGULAR,     false,  \

specs/tests/valgrind_unit_tests.py

@@ -1,7 +1,7 @@
 import sys, memcheck, argparse
 
 count_ALU_tests = 832
-count_processing_tests = 260
+count_processing_tests = 261
 count_token_tests = 17
 
 # Parse the one command line options