Add 'explicit' to most single argument constructors

This prevents implicit conversions that we do not want, such
as having a FileFd* being converted to a debListParser.

Two cases are not yet handled because they require changes
in code using them:

1. The classes in hashes.h
2. The URI class - this one is used quite a lot

1 files changed, 1 insertions, 1 deletions

diff --git a/apt-pkg/deb/debrecords.h b/apt-pkg/deb/debrecords.h
index 7c3b9020c..ea3fc320a 100644
--- a/apt-pkg/deb/debrecords.h
+++ b/apt-pkg/deb/debrecords.h
@@ -85,7 +85,7 @@ class APT_HIDDEN debDebFileRecordParser : public debRecordParserBase
  public:
    virtual std::string FileName() APT_OVERRIDE;
 
-   debDebFileRecordParser(std::string FileName);
+   explicit debDebFileRecordParser(std::string FileName);
    virtual ~debDebFileRecordParser();
 };