Fix trivial nitpicks
[Refactoring] Delaying throwing Exception makes control flow analysis simple
[Refactoring] Define enforceFmt
fix Issue 10254 - Purity correctness is broken with constructor
[appender] Reuse ensureAddable for reserve implementation

AFAICS, they have mostly same code.
[appender] Accepting qualified buffer is not safe behavior

To reduce existing code breaking, mark such construction as @system.
[appender] Determine @trusted operations
[parse, str.to!x] Determine @trusted operations
[formatValue] (bool, null, integrals, floatings, chars)

Floating point is blocked by sprintf
[non to!string] because they are unrelated to formatValue
[format] Add @safe/pure ability to writeUpToNextSpec, fillUp, and formattedWrite
[formatValue] (pointer)

+ Infer attributes in retro range primitives
[to!string] severals
[appender] Mark pointer slicing @trusted (fix for issue 10359)
Tabulation in line 48 causes make to fail.
Some version of make (ie: cygwin) will evaluate it to ^\t$, hence issuing an error.
Tabs replaced by 4 spaces.
Merge pull request #1375 from Geod24/master

Fix simple makefile error
Merge pull request #1337 from 9rnsr/fix_attrs

Potentially @safe & pure formatting
lastIndexOf with an index

comments and some tweaking

removed tabs

made the comments nicer

improvments derivated from comments

some bad stuff

found a bug I think

formatting