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, 2 insertions, 2 deletions

diff --git a/apt-pkg/contrib/progress.h b/apt-pkg/contrib/progress.h
index 4406a388b..903e6613e 100644
--- a/apt-pkg/contrib/progress.h
+++ b/apt-pkg/contrib/progress.h
@@ -80,9 +80,9 @@ class OpTextProgress : public OpProgress
 
    virtual void Done() APT_OVERRIDE;
    
-   OpTextProgress(bool NoUpdate = false) : NoUpdate(NoUpdate), 
+   explicit OpTextProgress(bool NoUpdate = false) : NoUpdate(NoUpdate),
                 NoDisplay(false), LastLen(0) {};
-   OpTextProgress(Configuration &Config);
+   explicit OpTextProgress(Configuration &Config);
    virtual ~OpTextProgress() {Done();};
 };