[lmi-commits] [lmi] master dca12e0 3/3: Note a possible use case for std::views

[Greg Chicares]

branch: master
commit dca12e060937de1372e181daa161fcb4a8a3070e
Author: Gregory W. Chicares <gchicares@sbcglobal.net>
Commit: Gregory W. Chicares <gchicares@sbcglobal.net>

    Note a possible use case for std::views
---
 ledger_invariant.cpp | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/ledger_invariant.cpp b/ledger_invariant.cpp
index 59e296d..1347d60 100644
--- a/ledger_invariant.cpp
+++ b/ledger_invariant.cpp
@@ -644,6 +644,12 @@ LedgerInvariant& LedgerInvariant::PlusEq(LedgerInvariant 
const& a_Addend)
     int Max = std::min(Length, a_Addend.Length);
 
     // ET !! This is of the form 'x = (lengthof x) take y'.
+    // C++2x provides std::views::{drop,take}, which are somewhat
+    // similar to APL's take and drop; however, for
+    //   x = (1 + lengthof(y) take y
+    // std::views would not extend the data with zeros, as APL would
+    // (in APL circles, that's called "overtake").
+    //
     // Make sure total (this) has enough years to add all years of a_Addend to.
     LMI_ASSERT(a_Addend.Length <= Length);
     for(int j = 0; j < Max; ++j)