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@Yardanico Yardanico/simple_log.nim

Last active Feb 3, 2019
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import strutils, times, terminal, macros
export strutils.format
LogLevel* = enum
lvlDebug = "DEBUG"
lvlInfo = "INFO"
lvlNotice = "NOTICE"
lvlWarn = "WARN"
lvlError = "ERROR"
lvlFatal = "FATAL"
# Logging level, can be changed
var logLevel* = lvlInfo
proc getColor(lvl: LogLevel): ForegroundColor =
## Gets color for the specified logging level
case lvl
of lvlDebug: fgWhite
of lvlInfo: fgGreen
of lvlNotice: fgCyan
of lvlWarn: fgYellow
of lvlError, lvlFatal: fgRed
proc log*(lvl: LogLevel, line: string) =
## Logs message with specified log level to the stdout
# Only print messages with specified log level or higher
if lvl < logLevel: return
setForegroundColor(stdout, getColor(lvl))
stdout.write("$1 | $2 | $3\n" % [$now(), $lvl, line])
macro getFormatted(data: varargs[untyped]): untyped =
## Returns a strutils.format call for code like
## getFormatted("Test", a = 1, b = "hello")
result = newTree(nnkCall)
var fmtString = ""
var i = 1
# List of arguments to a `format` call
var tmp = newSeq[NimNode]()
for arg in data:
# Literal string
if arg.kind == nnkStrLit:
fmtString &= arg.strVal
# a = b
elif arg.kind == nnkExprEqExpr:
fmtString &= ", " & arg[0].strVal & " = $" & $i
# Add nodes which will be used as arguments
for node in tmp:
template genTemplate(name: untyped, lvl: untyped): untyped =
template name*(data: varargs[untyped]): untyped =
log(lvl, getFormatted(data))
# Generate templates for all log levels
genTemplate(logDebug, lvlDebug)
genTemplate(logInfo, lvlInfo)
genTemplate(logNotice, lvlNotice)
genTemplate(logWarn, lvlWarn)
genTemplate(logError, lvlError)
genTemplate(logFatal, lvlFatal)
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