When converting a single integer to a string is `formatValue` preferred over `formattedWrite` in terms of compilation and run-time performance?

I would go with std.conv.to or std.conv.text :)

On Sun, Jan 6, 2019 at 10:55 PM Per Nordlöw 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?
>

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.

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.

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).

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!