Why is this string not concatenating?
@echo off
set NUM_NODES=4
set ENSEMBLE=127.0.0.1:2181
for /l %%x in (2, 1, %NUM_NODES%) do (
echo %%x
set ENSEMBLE=%ENSEMBLE%,127.0.0.1:2%%x81
)
echo ensemble: %ENSEMBLES%
OUTPUT:
2
3
4
ensemble: 127.0.0.1:2181,127.0.0.1:2481
Because in batch files variables are expanded when a command is parsed, not immediately prior to its execution. If you want the latter behaviour, you need to use delayed expansion:
setlocal enabledelayedexpansion
@echo off
set NUM_NODES=4
set ENSEMBLE=127.0.0.1:2181
for /l %%x in (2, 1, %NUM_NODES%) do (
echo %%x
set ENSEMBLE=!ENSEMBLE!,127.0.0.1:2%%x81
)
echo ensemble: %ENSEMBLES%
help set contains a lengthy description and exactly your example.
Both the original example and the answer contain the same typo, adding an S to the end of the variable in the ECHO statement, so neither example as it appears produces any output from the variable.
