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digitalmars.D.learn - Converting an integer to a string with std.format.

reply Per =?UTF-8?B?Tm9yZGzDtnc=?= <per.nordlow gmail.com> writes:
When converting a single integer to a string is `formatValue` 
preferred over `formattedWrite` in terms of compilation and 
run-time performance?
Jan 06
next sibling parent reply Daniel Kozak <kozzi11 gmail.com> writes:
I would go with std.conv.to or std.conv.text :)

On Sun, Jan 6, 2019 at 10:55 PM Per Nordl=C3=B6w via Digitalmars-d-learn <
digitalmars-d-learn puremagic.com> wrote:

 When converting a single integer to a string is `formatValue`
 preferred over `formattedWrite` in terms of compilation and
 run-time performance?
Jan 07
parent Per =?UTF-8?B?Tm9yZGzDtnc=?= <per.nordlow gmail.com> writes:
On Monday, 7 January 2019 at 09:57:45 UTC, Daniel Kozak wrote:
 I would go with std.conv.to or std.conv.text :)
The reason for not using std.conv.to is to prevent the extra allocation needed in code such as sink.put(someIntegral.to!string) instead of something like sink.putIntegralAsString(someIntegral) which should only extend the memory buffer of `sink` (via at most one allocation or reallocation).
Jan 07
prev sibling next sibling parent Vijay Nayar <madric gmail.com> writes:
On Sunday, 6 January 2019 at 21:53:31 UTC, Per Nordlöw wrote:
 When converting a single integer to a string is `formatValue` 
 preferred over `formattedWrite` in terms of compilation and 
 run-time performance?
Also, if you do not need to write to a stream or a range and just need the value, `format("%s", value)` works as well as std.conv's `to!string(value)`. But between the two functions, it seems that the only difference is that `formattedWrite` only accepts the exact values that go on the output range (such as an integer), and `formatValue` has extra logic to convert structs, classes, and unions into strings by calling their `toString()` method.
Jan 07
prev sibling parent reply Stefan Koch <uplink.coder googlemail.com> writes:
On Sunday, 6 January 2019 at 21:53:31 UTC, Per Nordlöw wrote:
 When converting a single integer to a string is `formatValue` 
 preferred over `formattedWrite` in terms of compilation and 
 run-time performance?
I've written my own itos function because using std.conv was too expensive. see https://github.com/UplinkCoder/dmd/blob/newCTFE_reboot_20741/src/ctfe/bc_common.d#L95 if you do want to convert longs you'll need a bigger pow_table as well as a diffrent log10 function.
Jan 07
parent Per =?UTF-8?B?Tm9yZGzDtnc=?= <per.nordlow gmail.com> writes:
On Monday, 7 January 2019 at 12:17:37 UTC, Stefan Koch wrote:
 I've written my own itos function because using std.conv was 
 too expensive.
 see 
 https://github.com/UplinkCoder/dmd/blob/newCTFE_reboot_20741/src/ctfe/bc_common.d#L95
Thanks!
Jan 07