diff --git a/ARR/ARR_BYTE.BAS b/ARR/ARR_BYTE.BAS
index 6ed98e9..af7dd2f 100644
--- a/ARR/ARR_BYTE.BAS
+++ b/ARR/ARR_BYTE.BAS
@@ -818,3 +818,37 @@ SUB ARR_BYTE.quicksort(arr%%(), start%, finish%, order%)
         CALL ARR_BYTE.quicksort(arr%%(), pivot% + 1, finish%, order%)
     END IF
 END SUB
+
+
+
+''
+' Combine two arrays - requires both array indexes are serial with no gaps
+' 
+' @param _BYTE ARRAY source_arr%%() array to combine
+' @param _BYTE ARRAY dest_arr%%() array to store combined result
+'
+SUB ARR_BYTE.union(source_arr%%(), dest_arr%%())
+    's = source, d = dest, n = new
+        'lb = lower bounds, ub = upper bounds
+        't = total elements
+    DIM AS LONG s_ub, s_lb, s_t
+    DIM AS LONG d_ub, d_lb, d_t
+    DIM AS LONG n_lb, n_ub, n_t
+    DIM AS LONG i, n
+
+    s_lb& = LBOUND(source_arr%%)
+    s_ub& = UBOUND(source_arr%%)
+    d_lb& = LBOUND(dest_arr%%)
+    d_ub& = UBOUND(dest_arr%%)
+    s_t&  = (s_ub& - s_lb&)
+    d_t&  = (d_ub& - d_lb&)
+    n_t&  = s_t& + d_t&
+    n_lb& = d_lb&
+    n_ub& = d_ub& + s_t& + 1
+    
+    REDIM _PRESERVE dest_arr(n_lb& TO n_ub&) AS _BYTE
+    FOR i& = s_lb& TO s_ub&
+        n& = d_ub& + 1 + i& - s_lb&
+        dest_arr%%(n&) = source_arr%%(i&)
+    NEXT i&
+END SUB
\ No newline at end of file
diff --git a/ARR/ARR_DBL.BAS b/ARR/ARR_DBL.BAS
index 7ff60e8..30ef452 100644
--- a/ARR/ARR_DBL.BAS
+++ b/ARR/ARR_DBL.BAS
@@ -818,3 +818,37 @@ SUB ARR_DBL.quicksort(arr#(), start%, finish%, order%)
         CALL ARR_DBL.quicksort(arr#(), pivot% + 1, finish%, order%)
     END IF
 END SUB
+
+
+
+''
+' Combine two arrays - requires both array indexes are serial with no gaps
+' 
+' @param DOUBLE ARRAY source_arr#() array to combine
+' @param DOUBLE ARRAY dest_arr#() array to store combined result
+'
+SUB ARR_DBL.union(source_arr#(), dest_arr#())
+    's = source, d = dest, n = new
+        'lb = lower bounds, ub = upper bounds
+        't = total elements
+    DIM AS LONG s_ub, s_lb, s_t
+    DIM AS LONG d_ub, d_lb, d_t
+    DIM AS LONG n_lb, n_ub, n_t
+    DIM AS LONG i, n
+
+    s_lb& = LBOUND(source_arr#)
+    s_ub& = UBOUND(source_arr#)
+    d_lb& = LBOUND(dest_arr#)
+    d_ub& = UBOUND(dest_arr#)
+    s_t&  = (s_ub& - s_lb&)
+    d_t&  = (d_ub& - d_lb&)
+    n_t&  = s_t& + d_t&
+    n_lb& = d_lb&
+    n_ub& = d_ub& + s_t& + 1
+    
+    REDIM _PRESERVE dest_arr(n_lb& TO n_ub&) AS DOUBLE
+    FOR i& = s_lb& TO s_ub&
+        n& = d_ub& + 1 + i& - s_lb&
+        dest_arr#(n&) = source_arr#(i&)
+    NEXT i&
+END SUB
\ No newline at end of file
diff --git a/ARR/ARR_FLT.BAS b/ARR/ARR_FLT.BAS
index be42619..89000cb 100644
--- a/ARR/ARR_FLT.BAS
+++ b/ARR/ARR_FLT.BAS
@@ -818,3 +818,37 @@ SUB ARR_FLT.quicksort(arr##(), start%, finish%, order%)
         CALL ARR_FLT.quicksort(arr##(), pivot% + 1, finish%, order%)
     END IF
 END SUB
+
+
+
+''
+' Combine two arrays - requires both array indexes are serial with no gaps
+' 
+' @param _FLOAT ARRAY source_arr##() array to combine
+' @param _FLOAT ARRAY dest_arr##() array to store combined result
+'
+SUB ARR_FLT.union(source_arr##(), dest_arr##())
+    's = source, d = dest, n = new
+        'lb = lower bounds, ub = upper bounds
+        't = total elements
+    DIM AS LONG s_ub, s_lb, s_t
+    DIM AS LONG d_ub, d_lb, d_t
+    DIM AS LONG n_lb, n_ub, n_t
+    DIM AS LONG i, n
+
+    s_lb& = LBOUND(source_arr##)
+    s_ub& = UBOUND(source_arr##)
+    d_lb& = LBOUND(dest_arr##)
+    d_ub& = UBOUND(dest_arr##)
+    s_t&  = (s_ub& - s_lb&)
+    d_t&  = (d_ub& - d_lb&)
+    n_t&  = s_t& + d_t&
+    n_lb& = d_lb&
+    n_ub& = d_ub& + s_t& + 1
+    
+    REDIM _PRESERVE dest_arr(n_lb& TO n_ub&) AS _FLOAT
+    FOR i& = s_lb& TO s_ub&
+        n& = d_ub& + 1 + i& - s_lb&
+        dest_arr##(n&) = source_arr##(i&)
+    NEXT i&
+END SUB
\ No newline at end of file
diff --git a/ARR/ARR_INT.BAS b/ARR/ARR_INT.BAS
index 39b6af1..50859c3 100644
--- a/ARR/ARR_INT.BAS
+++ b/ARR/ARR_INT.BAS
@@ -818,3 +818,37 @@ SUB ARR_INT.quicksort(arr%(), start%, finish%, order%)
         CALL ARR_INT.quicksort(arr%(), pivot% + 1, finish%, order%)
     END IF
 END SUB
+
+
+
+''
+' Combine two arrays - requires both array indexes are serial with no gaps
+' 
+' @param INTEGER ARRAY source_arr%() array to combine
+' @param INTEGER ARRAY dest_arr%() array to store combined result
+'
+SUB ARR_INT.union(source_arr%(), dest_arr%())
+    's = source, d = dest, n = new
+        'lb = lower bounds, ub = upper bounds
+        't = total elements
+    DIM AS LONG s_ub, s_lb, s_t
+    DIM AS LONG d_ub, d_lb, d_t
+    DIM AS LONG n_lb, n_ub, n_t
+    DIM AS LONG i, n
+
+    s_lb& = LBOUND(source_arr%)
+    s_ub& = UBOUND(source_arr%)
+    d_lb& = LBOUND(dest_arr%)
+    d_ub& = UBOUND(dest_arr%)
+    s_t&  = (s_ub& - s_lb&)
+    d_t&  = (d_ub& - d_lb&)
+    n_t&  = s_t& + d_t&
+    n_lb& = d_lb&
+    n_ub& = d_ub& + s_t& + 1
+    
+    REDIM _PRESERVE dest_arr(n_lb& TO n_ub&) AS INTEGER
+    FOR i& = s_lb& TO s_ub&
+        n& = d_ub& + 1 + i& - s_lb&
+        dest_arr%(n&) = source_arr%(i&)
+    NEXT i&
+END SUB
\ No newline at end of file
diff --git a/ARR/ARR_INT64.BAS b/ARR/ARR_INT64.BAS
index e4b3508..ca5f05a 100644
--- a/ARR/ARR_INT64.BAS
+++ b/ARR/ARR_INT64.BAS
@@ -818,3 +818,37 @@ SUB ARR_INT64.quicksort(arr&&(), start%, finish%, order%)
         CALL ARR_INT64.quicksort(arr&&(), pivot% + 1, finish%, order%)
     END IF
 END SUB
+
+
+
+''
+' Combine two arrays - requires both array indexes are serial with no gaps
+' 
+' @param _INTEGER64 ARRAY source_arr&&() array to combine
+' @param _INTEGER64 ARRAY dest_arr&&() array to store combined result
+'
+SUB ARR_INT64.union(source_arr&&(), dest_arr&&())
+    's = source, d = dest, n = new
+        'lb = lower bounds, ub = upper bounds
+        't = total elements
+    DIM AS LONG s_ub, s_lb, s_t
+    DIM AS LONG d_ub, d_lb, d_t
+    DIM AS LONG n_lb, n_ub, n_t
+    DIM AS LONG i, n
+
+    s_lb& = LBOUND(source_arr&&)
+    s_ub& = UBOUND(source_arr&&)
+    d_lb& = LBOUND(dest_arr&&)
+    d_ub& = UBOUND(dest_arr&&)
+    s_t&  = (s_ub& - s_lb&)
+    d_t&  = (d_ub& - d_lb&)
+    n_t&  = s_t& + d_t&
+    n_lb& = d_lb&
+    n_ub& = d_ub& + s_t& + 1
+    
+    REDIM _PRESERVE dest_arr(n_lb& TO n_ub&) AS _INTEGER64
+    FOR i& = s_lb& TO s_ub&
+        n& = d_ub& + 1 + i& - s_lb&
+        dest_arr&&(n&) = source_arr&&(i&)
+    NEXT i&
+END SUB
\ No newline at end of file
diff --git a/ARR/ARR_LONG.BAS b/ARR/ARR_LONG.BAS
index 49cface..e33baaa 100644
--- a/ARR/ARR_LONG.BAS
+++ b/ARR/ARR_LONG.BAS
@@ -818,3 +818,37 @@ SUB ARR_LONG.quicksort(arr&(), start%, finish%, order%)
         CALL ARR_LONG.quicksort(arr&(), pivot% + 1, finish%, order%)
     END IF
 END SUB
+
+
+
+''
+' Combine two arrays - requires both array indexes are serial with no gaps
+' 
+' @param LONG ARRAY source_arr&() array to combine
+' @param LONG ARRAY dest_arr&() array to store combined result
+'
+SUB ARR_LONG.union(source_arr&(), dest_arr&())
+    's = source, d = dest, n = new
+        'lb = lower bounds, ub = upper bounds
+        't = total elements
+    DIM AS LONG s_ub, s_lb, s_t
+    DIM AS LONG d_ub, d_lb, d_t
+    DIM AS LONG n_lb, n_ub, n_t
+    DIM AS LONG i, n
+
+    s_lb& = LBOUND(source_arr&)
+    s_ub& = UBOUND(source_arr&)
+    d_lb& = LBOUND(dest_arr&)
+    d_ub& = UBOUND(dest_arr&)
+    s_t&  = (s_ub& - s_lb&)
+    d_t&  = (d_ub& - d_lb&)
+    n_t&  = s_t& + d_t&
+    n_lb& = d_lb&
+    n_ub& = d_ub& + s_t& + 1
+    
+    REDIM _PRESERVE dest_arr(n_lb& TO n_ub&) AS LONG
+    FOR i& = s_lb& TO s_ub&
+        n& = d_ub& + 1 + i& - s_lb&
+        dest_arr&(n&) = source_arr&(i&)
+    NEXT i&
+END SUB
\ No newline at end of file
diff --git a/ARR/ARR_SNG.BAS b/ARR/ARR_SNG.BAS
index 6e837e3..b8de88b 100644
--- a/ARR/ARR_SNG.BAS
+++ b/ARR/ARR_SNG.BAS
@@ -818,3 +818,37 @@ SUB ARR_SNG.quicksort(arr!(), start%, finish%, order%)
         CALL ARR_SNG.quicksort(arr!(), pivot% + 1, finish%, order%)
     END IF
 END SUB
+
+
+
+''
+' Combine two arrays - requires both array indexes are serial with no gaps
+' 
+' @param SINGLE ARRAY source_arr!() array to combine
+' @param SINGLE ARRAY dest_arr!() array to store combined result
+'
+SUB ARR_SNG.union(source_arr!(), dest_arr!())
+    's = source, d = dest, n = new
+        'lb = lower bounds, ub = upper bounds
+        't = total elements
+    DIM AS LONG s_ub, s_lb, s_t
+    DIM AS LONG d_ub, d_lb, d_t
+    DIM AS LONG n_lb, n_ub, n_t
+    DIM AS LONG i, n
+
+    s_lb& = LBOUND(source_arr!)
+    s_ub& = UBOUND(source_arr!)
+    d_lb& = LBOUND(dest_arr!)
+    d_ub& = UBOUND(dest_arr!)
+    s_t&  = (s_ub& - s_lb&)
+    d_t&  = (d_ub& - d_lb&)
+    n_t&  = s_t& + d_t&
+    n_lb& = d_lb&
+    n_ub& = d_ub& + s_t& + 1
+    
+    REDIM _PRESERVE dest_arr(n_lb& TO n_ub&) AS SINGLE
+    FOR i& = s_lb& TO s_ub&
+        n& = d_ub& + 1 + i& - s_lb&
+        dest_arr!(n&) = source_arr!(i&)
+    NEXT i&
+END SUB
\ No newline at end of file
diff --git a/ARR/ARR_STR.BAS b/ARR/ARR_STR.BAS
index d948cdb..f90593e 100644
--- a/ARR/ARR_STR.BAS
+++ b/ARR/ARR_STR.BAS
@@ -623,3 +623,36 @@ SUB ARR_STR.quicksort(arr$(), start%, finish%, order%)
         CALL ARR_STR.quicksort(arr$(), pivot% + 1, finish%, order%)
     END IF
 END SUB
+
+
+''
+' Combine two arrays - requires both array indexes are serial with no gaps
+' 
+' @param STRING ARRAY source_arr$() array to combine
+' @param STRING ARRAY dest_arr$() array to store combined result
+'
+SUB ARR_STR.union(source_arr$(), dest_arr$())
+    's = source, d = dest, n = new
+        'lb = lower bounds, ub = upper bounds
+        't = total elements
+    DIM AS LONG s_ub, s_lb, s_t
+    DIM AS LONG d_ub, d_lb, d_t
+    DIM AS LONG n_lb, n_ub, n_t
+    DIM AS LONG i, n
+
+    s_lb& = LBOUND(source_arr$)
+    s_ub& = UBOUND(source_arr$)
+    d_lb& = LBOUND(dest_arr$)
+    d_ub& = UBOUND(dest_arr$)
+    s_t&  = (s_ub& - s_lb&)
+    d_t&  = (d_ub& - d_lb&)
+    n_t&  = s_t& + d_t&
+    n_lb& = d_lb&
+    n_ub& = d_ub& + s_t& + 1
+    
+    REDIM _PRESERVE dest_arr(n_lb& TO n_ub&) AS STRING
+    FOR i& = s_lb& TO s_ub&
+        n& = d_ub& + 1 + i& - s_lb&
+        dest_arr$(n&) = source_arr$(i&)
+    NEXT i&
+END SUB
\ No newline at end of file
diff --git a/ARR/ARR_TEMPLATE.BAS b/ARR/ARR_TEMPLATE.BAS
index 2fc8432..a1b2a60 100644
--- a/ARR/ARR_TEMPLATE.BAS
+++ b/ARR/ARR_TEMPLATE.BAS
@@ -818,3 +818,37 @@ SUB ARR_{UT}.quicksort(arr{SY}(), start%, finish%, order%)
         CALL ARR_{UT}.quicksort(arr{SY}(), pivot% + 1, finish%, order%)
     END IF
 END SUB
+
+
+
+''
+' Combine two arrays - requires both array indexes are serial with no gaps
+' 
+' @param {Q} ARRAY source_arr{SY}() array to combine
+' @param {Q} ARRAY dest_arr{SY}() array to store combined result
+'
+SUB ARR_{UT}.union(source_arr{SY}(), dest_arr{SY}())
+    's = source, d = dest, n = new
+        'lb = lower bounds, ub = upper bounds
+        't = total elements
+    DIM AS LONG s_ub, s_lb, s_t
+    DIM AS LONG d_ub, d_lb, d_t
+    DIM AS LONG n_lb, n_ub, n_t
+    DIM AS LONG i, n
+
+    s_lb& = LBOUND(source_arr{SY})
+    s_ub& = UBOUND(source_arr{SY})
+    d_lb& = LBOUND(dest_arr{SY})
+    d_ub& = UBOUND(dest_arr{SY})
+    s_t&  = (s_ub& - s_lb&)
+    d_t&  = (d_ub& - d_lb&)
+    n_t&  = s_t& + d_t&
+    n_lb& = d_lb&
+    n_ub& = d_ub& + s_t& + 1
+    
+    REDIM _PRESERVE dest_arr(n_lb& TO n_ub&) AS {Q}
+    FOR i& = s_lb& TO s_ub&
+        n& = d_ub& + 1 + i& - s_lb&
+        dest_arr{SY}(n&) = source_arr{SY}(i&)
+    NEXT i&
+END SUB
\ No newline at end of file
diff --git a/ARR/ARR_UBYTE.BAS b/ARR/ARR_UBYTE.BAS
index 9b6c0bd..bb588ec 100644
--- a/ARR/ARR_UBYTE.BAS
+++ b/ARR/ARR_UBYTE.BAS
@@ -818,3 +818,37 @@ SUB ARR_UBYTE.quicksort(arr~%%(), start%, finish%, order%)
         CALL ARR_UBYTE.quicksort(arr~%%(), pivot% + 1, finish%, order%)
     END IF
 END SUB
+
+
+
+''
+' Combine two arrays - requires both array indexes are serial with no gaps
+' 
+' @param _UNSIGNED _BYTE ARRAY source_arr~%%() array to combine
+' @param _UNSIGNED _BYTE ARRAY dest_arr~%%() array to store combined result
+'
+SUB ARR_UBYTE.union(source_arr~%%(), dest_arr~%%())
+    's = source, d = dest, n = new
+        'lb = lower bounds, ub = upper bounds
+        't = total elements
+    DIM AS LONG s_ub, s_lb, s_t
+    DIM AS LONG d_ub, d_lb, d_t
+    DIM AS LONG n_lb, n_ub, n_t
+    DIM AS LONG i, n
+
+    s_lb& = LBOUND(source_arr~%%)
+    s_ub& = UBOUND(source_arr~%%)
+    d_lb& = LBOUND(dest_arr~%%)
+    d_ub& = UBOUND(dest_arr~%%)
+    s_t&  = (s_ub& - s_lb&)
+    d_t&  = (d_ub& - d_lb&)
+    n_t&  = s_t& + d_t&
+    n_lb& = d_lb&
+    n_ub& = d_ub& + s_t& + 1
+    
+    REDIM _PRESERVE dest_arr(n_lb& TO n_ub&) AS _UNSIGNED _BYTE
+    FOR i& = s_lb& TO s_ub&
+        n& = d_ub& + 1 + i& - s_lb&
+        dest_arr~%%(n&) = source_arr~%%(i&)
+    NEXT i&
+END SUB
\ No newline at end of file
diff --git a/ARR/ARR_UINT.BAS b/ARR/ARR_UINT.BAS
index a3a3627..b85041b 100644
--- a/ARR/ARR_UINT.BAS
+++ b/ARR/ARR_UINT.BAS
@@ -818,3 +818,37 @@ SUB ARR_UINT.quicksort(arr~%(), start%, finish%, order%)
         CALL ARR_UINT.quicksort(arr~%(), pivot% + 1, finish%, order%)
     END IF
 END SUB
+
+
+
+''
+' Combine two arrays - requires both array indexes are serial with no gaps
+' 
+' @param _UNSIGNED INTEGER ARRAY source_arr~%() array to combine
+' @param _UNSIGNED INTEGER ARRAY dest_arr~%() array to store combined result
+'
+SUB ARR_UINT.union(source_arr~%(), dest_arr~%())
+    's = source, d = dest, n = new
+        'lb = lower bounds, ub = upper bounds
+        't = total elements
+    DIM AS LONG s_ub, s_lb, s_t
+    DIM AS LONG d_ub, d_lb, d_t
+    DIM AS LONG n_lb, n_ub, n_t
+    DIM AS LONG i, n
+
+    s_lb& = LBOUND(source_arr~%)
+    s_ub& = UBOUND(source_arr~%)
+    d_lb& = LBOUND(dest_arr~%)
+    d_ub& = UBOUND(dest_arr~%)
+    s_t&  = (s_ub& - s_lb&)
+    d_t&  = (d_ub& - d_lb&)
+    n_t&  = s_t& + d_t&
+    n_lb& = d_lb&
+    n_ub& = d_ub& + s_t& + 1
+    
+    REDIM _PRESERVE dest_arr(n_lb& TO n_ub&) AS _UNSIGNED INTEGER
+    FOR i& = s_lb& TO s_ub&
+        n& = d_ub& + 1 + i& - s_lb&
+        dest_arr~%(n&) = source_arr~%(i&)
+    NEXT i&
+END SUB
\ No newline at end of file
diff --git a/ARR/ARR_UINT64.BAS b/ARR/ARR_UINT64.BAS
index 597335f..7bcd651 100644
--- a/ARR/ARR_UINT64.BAS
+++ b/ARR/ARR_UINT64.BAS
@@ -818,3 +818,37 @@ SUB ARR_UINT64.quicksort(arr~&&(), start%, finish%, order%)
         CALL ARR_UINT64.quicksort(arr~&&(), pivot% + 1, finish%, order%)
     END IF
 END SUB
+
+
+
+''
+' Combine two arrays - requires both array indexes are serial with no gaps
+' 
+' @param _UNSIGNED _INTEGER64 ARRAY source_arr~&&() array to combine
+' @param _UNSIGNED _INTEGER64 ARRAY dest_arr~&&() array to store combined result
+'
+SUB ARR_UINT64.union(source_arr~&&(), dest_arr~&&())
+    's = source, d = dest, n = new
+        'lb = lower bounds, ub = upper bounds
+        't = total elements
+    DIM AS LONG s_ub, s_lb, s_t
+    DIM AS LONG d_ub, d_lb, d_t
+    DIM AS LONG n_lb, n_ub, n_t
+    DIM AS LONG i, n
+
+    s_lb& = LBOUND(source_arr~&&)
+    s_ub& = UBOUND(source_arr~&&)
+    d_lb& = LBOUND(dest_arr~&&)
+    d_ub& = UBOUND(dest_arr~&&)
+    s_t&  = (s_ub& - s_lb&)
+    d_t&  = (d_ub& - d_lb&)
+    n_t&  = s_t& + d_t&
+    n_lb& = d_lb&
+    n_ub& = d_ub& + s_t& + 1
+    
+    REDIM _PRESERVE dest_arr(n_lb& TO n_ub&) AS _UNSIGNED _INTEGER64
+    FOR i& = s_lb& TO s_ub&
+        n& = d_ub& + 1 + i& - s_lb&
+        dest_arr~&&(n&) = source_arr~&&(i&)
+    NEXT i&
+END SUB
\ No newline at end of file
diff --git a/ARR/ARR_ULONG.BAS b/ARR/ARR_ULONG.BAS
index a75a678..19d749e 100644
--- a/ARR/ARR_ULONG.BAS
+++ b/ARR/ARR_ULONG.BAS
@@ -818,3 +818,37 @@ SUB ARR_ULONG.quicksort(arr~&(), start%, finish%, order%)
         CALL ARR_ULONG.quicksort(arr~&(), pivot% + 1, finish%, order%)
     END IF
 END SUB
+
+
+
+''
+' Combine two arrays - requires both array indexes are serial with no gaps
+' 
+' @param _UNSIGNED LONG ARRAY source_arr~&() array to combine
+' @param _UNSIGNED LONG ARRAY dest_arr~&() array to store combined result
+'
+SUB ARR_ULONG.union(source_arr~&(), dest_arr~&())
+    's = source, d = dest, n = new
+        'lb = lower bounds, ub = upper bounds
+        't = total elements
+    DIM AS LONG s_ub, s_lb, s_t
+    DIM AS LONG d_ub, d_lb, d_t
+    DIM AS LONG n_lb, n_ub, n_t
+    DIM AS LONG i, n
+
+    s_lb& = LBOUND(source_arr~&)
+    s_ub& = UBOUND(source_arr~&)
+    d_lb& = LBOUND(dest_arr~&)
+    d_ub& = UBOUND(dest_arr~&)
+    s_t&  = (s_ub& - s_lb&)
+    d_t&  = (d_ub& - d_lb&)
+    n_t&  = s_t& + d_t&
+    n_lb& = d_lb&
+    n_ub& = d_ub& + s_t& + 1
+    
+    REDIM _PRESERVE dest_arr(n_lb& TO n_ub&) AS _UNSIGNED LONG
+    FOR i& = s_lb& TO s_ub&
+        n& = d_ub& + 1 + i& - s_lb&
+        dest_arr~&(n&) = source_arr~&(i&)
+    NEXT i&
+END SUB
\ No newline at end of file
diff --git a/ARR/README.md b/ARR/README.md
index 3eb0cb4..0fbdafe 100644
--- a/ARR/README.md
+++ b/ARR/README.md
@@ -78,6 +78,7 @@ A bunch of very handy stuff for arrays spanning all QB64 types.
 | `.between` | Return elements between a start and end index in an array |
 | `.sort` | Sort elements of an array in ascending order |
 | `.rsort` | Sort elements of an array in desscending order |
+| `.union` | Combine two arrays - requires both array indexes are serial with no gaps |
 
 ### SUBS AND FUNCTIONS FOR STRING TYPE:
 | SUB / FUNCTION | NOTES |
@@ -112,9 +113,9 @@ A bunch of very handy stuff for arrays spanning all QB64 types.
 | `.between` | Return elements between a start and end index in an array |
 | `.sort` | Sort elements of an array in ascending order |
 | `.rsort` | Sort elements of an array in desscending order |
+| `.union` | Combine two arrays - requires both array indexes are serial with no gaps |
 
 
 ### TO DO
-- [ ] .union
 - [ ] .intersection
 - [ ] .difference
\ No newline at end of file
diff --git a/ARR/TEST-ARR_BYTE.BAS.bas b/ARR/TEST-ARR_BYTE.BAS.bas
new file mode 100644
index 0000000..b9251ee
--- /dev/null
+++ b/ARR/TEST-ARR_BYTE.BAS.bas
@@ -0,0 +1,36 @@
+
+OPTION _EXPLICIT
+'$DYNAMIC
+
+'$INCLUDE:'include/QB64_GJ_LIB/_GJ_LIB.BI'
+
+$CONSOLE:ONLY
+_CONSOLE ON
+
+DIM arr1(1 TO 5) AS _BYTE
+DIM arr2(6 TO 10) AS _BYTE
+DIM arr3(11 TO 20) AS _BYTE
+
+DIM i AS LONG
+
+FOR i& = LBOUND(arr1%%) TO UBOUND(arr1%%)
+	arr1%%(i&) = i&
+NEXT i&
+
+FOR i& = LBOUND(arr2%%) TO UBOUND(arr2%%)
+	arr2%%(i&) = i&
+NEXT i&
+
+FOR i& = LBOUND(arr3%%) TO UBOUND(arr3%%)
+	arr3%%(i&) = i&
+NEXT i&
+
+PRINT DUMP.byte_array$(arr1%%(), "arr1%%()")
+PRINT DUMP.byte_array$(arr2%%(), "arr2%%()")
+PRINT DUMP.byte_array$(arr3%%(), "arr3%%()")
+CALL ARR_BYTE.union(arr2%%(), arr1%%())
+CALL ARR_BYTE.union(arr3%%(), arr1%%())
+PRINT DUMP.byte_array$(arr1%%(), "arr1%%() (post union) ")
+SYSTEM
+
+'$INCLUDE:'include/QB64_GJ_LIB/_GJ_LIB.BM'
diff --git a/ARR/TEST-ARR_STR.BAS.bas b/ARR/TEST-ARR_STR.BAS.bas
new file mode 100644
index 0000000..87eaab7
--- /dev/null
+++ b/ARR/TEST-ARR_STR.BAS.bas
@@ -0,0 +1,36 @@
+
+OPTION _EXPLICIT
+'$DYNAMIC
+
+'$INCLUDE:'include/QB64_GJ_LIB/_GJ_LIB.BI'
+
+$CONSOLE:ONLY
+_CONSOLE ON
+
+DIM arr1(1 TO 5) AS STRING
+DIM arr2(6 TO 10) AS STRING
+DIM arr3(11 TO 20) AS STRING
+
+DIM i AS LONG
+
+FOR i& = LBOUND(arr1$) TO UBOUND(arr1$)
+	arr1$(i&) = _TRIM$(STR$(i&))
+NEXT i&
+
+FOR i& = LBOUND(arr2$) TO UBOUND(arr2$)
+	arr2$(i&) = _TRIM$(STR$(i&))
+NEXT i&
+
+FOR i& = LBOUND(arr3$) TO UBOUND(arr3$)
+	arr3$(i&) = _TRIM$(STR$(i&))
+NEXT i&
+
+PRINT DUMP.string_array$(arr1$(), "arr1$()")
+PRINT DUMP.string_array$(arr2$(), "arr2$()")
+PRINT DUMP.string_array$(arr3$(), "arr3$()")
+CALL ARR_STR.union(arr2$(), arr1$())
+CALL ARR_STR.union(arr3$(), arr1$())
+PRINT DUMP.string_array$(arr1$(), "arr1$() (post union) ")
+SYSTEM
+
+'$INCLUDE:'include/QB64_GJ_LIB/_GJ_LIB.BM'
diff --git a/ARR/generate.sh b/ARR/generate.sh
index 1f648b1..c0e272c 100755
--- a/ARR/generate.sh
+++ b/ARR/generate.sh
@@ -3,7 +3,7 @@
 # generate was used on MacOS - so gnu-sed is needed on MacOS:
 # brew install gnu-sed
 # on linux, just replace $SED with sed
-SED=gsed
+SED=sed
 
 TYPES=(
     BYTE
diff --git a/_GJ_LIB_COMMON.BI b/_GJ_LIB_COMMON.BI
index 0cfa86d..ff943e3 100644
--- a/_GJ_LIB_COMMON.BI
+++ b/_GJ_LIB_COMMON.BI
@@ -13,10 +13,12 @@ $IF FALSE = UNDEFINED AND TRUE = UNDEFINED THEN
 $END IF
 
 $IF SLASH = UNDEFINED THEN
-    $IF WIN AND SLASH THEN
-        CONST SLASH$ = "\"
-    $ELSE
+    $IF MAC THEN
         CONST SLASH$ = "/"
+    $ELSEIF LINUX THEN
+        CONST SLASH$ = "/"
+    $ELSEIF WIN THEN
+        CONST SLASH$ = "\"
     $END IF 
 $END IF