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Protos

std:logging/TextFormatter

std:logging/TextFormatter

Section titled “std:logging/TextFormatter”

Canonical occurrence: protos/lib/logging/TextFormatter.protos · Protos revision: e99b712ecf658a527b1fe82c8beba2c1286d8dc9.

Deterministic plain-text rendering of std:logging/LogEvent values. Each event renders as exactly one line with no line terminator, source metadata, color, or terminal control sequence:

LINE  = [TIMESTAMP " "] LEVEL " " STRING [" " MAP] [" error=true"]
VALUE = "null" | "true" | "false" | INTEGER | FLOAT | STRING | ARRAY | MAP
ARRAY = "[" [VALUE (", " VALUE)*] "]"
MAP   = "{" [STRING "=" VALUE (", " STRING "=" VALUE)*] "}"

For example ERROR "request failed" {"requestId"="r-7"} error=true.

TIMESTAMP appears exactly when the event has a timestamp and is std:datetime/ISO8601.formatInstant of it, in UTC with the Z designator, for example 1970-01-01T00:00:00.000000001Z DEBUG "tick". An instant outside the civil range that format supports signals an Error; there is no other timestamp spelling.

The fields Map is omitted when empty, and error=true appears exactly when an Error is attached; the attached Error is never inspected, so every Error renders the same marker, distinct from a field named "error".

Strings, including the message and Map keys, are double-quoted. ", \, LF, CR, and TAB render as \", \\, \n, \r, and \t; the remaining C0 controls, DEL, the C1 controls U+0080 to U+009F, U+2028, and U+2029 render as \u{HEX} with uppercase hexadecimal digits and no leading zeros. Every other Unicode scalar is kept exactly, without normalization.

Map entries render in ascending order of their keys’ Unicode scalar sequences: the first differing scalar decides, and a proper prefix comes first. The same order applies at every depth; Map iteration order never matters.

Integers render in canonical base 10. Floats render as NaN, Infinity, -Infinity, 0.0, -0.0, or, for other values, from the decimal with the fewest significant digits that round-trips to the same binary64 value (the closest such decimal; an exact tie takes the even last digit). With digits d (k of them) and value d * 10^(n - k), the layout is d followed by n - k zeros and .0 when k <= n <= 21; d with a . after its first n digits when 0 < n <= 21; 0., -n zeros, and d when -6 < n <= 0; and otherwise the first digit, . and the remaining digits when k > 1, then e, the sign + or -, and |n - 1|. A negative value is prefixed with -. Every finite Float therefore renders with a . or an exponent and never looks like an Integer.

Observable top-level slots

Section titled “Observable top-level slots”

This page lists the complete mechanically observable top-level slot inventory required by D067. Authored documentation, when present, is canonical D062 prose; mechanical presence alone does not create a stability or compatibility promise.

format

Section titled “format”

Answers the plain-text line of event, which must be recognized by std:logging/LogEvent; any other argument, or a timestamp that std:datetime/ISO8601.formatInstant cannot write, signals an Error. Rendering invokes no behavior stored in the event.

Mechanical facts

Section titled “Mechanical facts”

No callable shape is mechanically recorded for this slot.

Exact module source · Standard-library API · Standard library overview