Procs

proc get_terminal_size(fallback = (80, 24)): terminal_size {....raises: [],
    tags: [ReadEnvEffect], forbids: [].}

Hint: this does not simply refer to environment variable,

call os.get_terminal_size. This is a wrapper around terminalSize of std/terminal, which is more steady, returning meaningful result even when stdout is not associatd with a terminal.

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