%d

[uiop via Digitalmars-d]

On Monday, 9 November 2015 at 20:22:53 UTC, M Murray wrote:
> explane

'd' stands for decimal (base 10 integer). It instructs the parser 
to scan and convert the argument in a certain way.

'%' is one of the symbol typically used for string interpolation 
(like $), but it looks like the first programming language that 
implemented the format specifier based on the percent symbol was 
BCPL[1], then followed by all the other lang.

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[1]
In this page the format %<letter> seems to appear from BCPL:
https://en.wikipedia.org/wiki/Printf_format_string#1960s:_BCPL.2C_ALGOL_68.2C_Multics_PL.2FI
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